literature review in research papers

Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, generate accurate citations for free.

Knowledge Base

Methodology

How to Write a Literature Review | Guide, Examples, & Templates

How to Write a Literature Review | Guide, Examples, & Templates

Published on January 2, 2023 by Shona McCombes . Revised on September 11, 2023.

What is a literature review? A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research that you can later apply to your paper, thesis, or dissertation topic .

There are five key steps to writing a literature review:

Search for relevant literature
Evaluate sources
Identify themes, debates, and gaps
Outline the structure
Write your literature review

A good literature review doesn’t just summarize sources—it analyzes, synthesizes , and critically evaluates to give a clear picture of the state of knowledge on the subject.

Instantly correct all language mistakes in your text

Upload your document to correct all your mistakes in minutes

What is the purpose of a literature review, examples of literature reviews, step 1 – search for relevant literature, step 2 – evaluate and select sources, step 3 – identify themes, debates, and gaps, step 4 – outline your literature review’s structure, step 5 – write your literature review, free lecture slides, other interesting articles, frequently asked questions, introduction.

Quick Run-through
Step 1 & 2

When you write a thesis , dissertation , or research paper , you will likely have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

Demonstrate your familiarity with the topic and its scholarly context
Develop a theoretical framework and methodology for your research
Position your work in relation to other researchers and theorists
Show how your research addresses a gap or contributes to a debate
Evaluate the current state of research and demonstrate your knowledge of the scholarly debates around your topic.

Writing literature reviews is a particularly important skill if you want to apply for graduate school or pursue a career in research. We’ve written a step-by-step guide that you can follow below.

Here's why students love Scribbr's proofreading services

Discover proofreading & editing

Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research problem and questions .

Make a list of keywords

Start by creating a list of keywords related to your research question. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list as you discover new keywords in the process of your literature search.

Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
Body image, self-perception, self-esteem, mental health
Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some useful databases to search for journals and articles include:

Your university’s library catalogue
Google Scholar
Project Muse (humanities and social sciences)
Medline (life sciences and biomedicine)
EconLit (economics)
Inspec (physics, engineering and computer science)

You can also use boolean operators to help narrow down your search.

Make sure to read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

You likely won’t be able to read absolutely everything that has been written on your topic, so it will be necessary to evaluate which sources are most relevant to your research question.

For each publication, ask yourself:

What question or problem is the author addressing?
What are the key concepts and how are they defined?
What are the key theories, models, and methods?
Does the research use established frameworks or take an innovative approach?
What are the results and conclusions of the study?
How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
What are the strengths and weaknesses of the research?

Make sure the sources you use are credible , and make sure you read any landmark studies and major theories in your field of research.

You can use our template to summarize and evaluate sources you’re thinking about using. Click on either button below to download.

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It is important to keep track of your sources with citations to avoid plagiarism . It can be helpful to make an annotated bibliography , where you compile full citation information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

The only proofreading tool specialized in correcting academic writing - try for free!

The academic proofreading tool has been trained on 1000s of academic texts and by native English editors. Making it the most accurate and reliable proofreading tool for students.

Try for free

To begin organizing your literature review’s argument and structure, be sure you understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
Themes: what questions or concepts recur across the literature?
Debates, conflicts and contradictions: where do sources disagree?
Pivotal publications: are there any influential theories or studies that changed the direction of the field?
Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

Most research has focused on young women.
There is an increasing interest in the visual aspects of social media.
But there is still a lack of robust research on highly visual platforms like Instagram and Snapchat—this is a gap that you could address in your own research.

There are various approaches to organizing the body of a literature review. Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarizing sources in order.

Try to analyze patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organize your literature review into subsections that address different aspects of the topic.

For example, if you are reviewing literature about inequalities in migrant health outcomes, key themes might include healthcare policy, language barriers, cultural attitudes, legal status, and economic access.

Methodological

If you draw your sources from different disciplines or fields that use a variety of research methods , you might want to compare the results and conclusions that emerge from different approaches. For example:

Look at what results have emerged in qualitative versus quantitative research
Discuss how the topic has been approached by empirical versus theoretical scholarship
Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text , your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, you can follow these tips:

Summarize and synthesize: give an overview of the main points of each source and combine them into a coherent whole
Analyze and interpret: don’t just paraphrase other researchers — add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
Critically evaluate: mention the strengths and weaknesses of your sources
Write in well-structured paragraphs: use transition words and topic sentences to draw connections, comparisons and contrasts

In the conclusion, you should summarize the key findings you have taken from the literature and emphasize their significance.

When you’ve finished writing and revising your literature review, don’t forget to proofread thoroughly before submitting. Not a language expert? Check out Scribbr’s professional proofreading services !

This article has been adapted into lecture slides that you can use to teach your students about writing a literature review.

Scribbr slides are free to use, customize, and distribute for educational purposes.

Open Google Slides Download PowerPoint

If you want to know more about the research process , methodology , research bias , or statistics , make sure to check out some of our other articles with explanations and examples.

Sampling methods
Simple random sampling
Stratified sampling
Cluster sampling
Likert scales
Reproducibility

Statistics

Null hypothesis
Statistical power
Probability distribution
Effect size
Poisson distribution

Research bias

Optimism bias
Cognitive bias
Implicit bias
Hawthorne effect
Anchoring bias
Explicit bias

A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a thesis, dissertation , or research paper , in order to situate your work in relation to existing knowledge.

There are several reasons to conduct a literature review at the beginning of a research project:

To familiarize yourself with the current state of knowledge on your topic
To ensure that you’re not just repeating what others have already done
To identify gaps in knowledge and unresolved problems that your research can address
To develop your theoretical framework and methodology
To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your thesis or dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

A literature review is a survey of credible sources on a topic, often used in dissertations , theses, and research papers . Literature reviews give an overview of knowledge on a subject, helping you identify relevant theories and methods, as well as gaps in existing research. Literature reviews are set up similarly to other academic texts , with an introduction , a main body, and a conclusion .

An annotated bibliography is a list of source references that has a short description (called an annotation ) for each of the sources. It is often assigned as part of the research process for a paper .

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the “Cite this Scribbr article” button to automatically add the citation to our free Citation Generator.

McCombes, S. (2023, September 11). How to Write a Literature Review | Guide, Examples, & Templates. Scribbr. Retrieved April 9, 2024, from https://www.scribbr.com/dissertation/literature-review/

Is this article helpful?

Shona McCombes

Other students also liked, what is a theoretical framework | guide to organizing, what is a research methodology | steps & tips, how to write a research proposal | examples & templates, unlimited academic ai-proofreading.

✔ Document error-free in 5minutes ✔ Unlimited document corrections ✔ Specialized in correcting academic texts

Purdue Online Writing Lab Purdue OWL® College of Liberal Arts

Writing a Literature Review

Welcome to the Purdue OWL

This page is brought to you by the OWL at Purdue University. When printing this page, you must include the entire legal notice.

Copyright ©1995-2018 by The Writing Lab & The OWL at Purdue and Purdue University. All rights reserved. This material may not be published, reproduced, broadcast, rewritten, or redistributed without permission. Use of this site constitutes acceptance of our terms and conditions of fair use.

A literature review is a document or section of a document that collects key sources on a topic and discusses those sources in conversation with each other (also called synthesis ). The lit review is an important genre in many disciplines, not just literature (i.e., the study of works of literature such as novels and plays). When we say “literature review” or refer to “the literature,” we are talking about the research ( scholarship ) in a given field. You will often see the terms “the research,” “the scholarship,” and “the literature” used mostly interchangeably.

Where, when, and why would I write a lit review?

There are a number of different situations where you might write a literature review, each with slightly different expectations; different disciplines, too, have field-specific expectations for what a literature review is and does. For instance, in the humanities, authors might include more overt argumentation and interpretation of source material in their literature reviews, whereas in the sciences, authors are more likely to report study designs and results in their literature reviews; these differences reflect these disciplines’ purposes and conventions in scholarship. You should always look at examples from your own discipline and talk to professors or mentors in your field to be sure you understand your discipline’s conventions, for literature reviews as well as for any other genre.

A literature review can be a part of a research paper or scholarly article, usually falling after the introduction and before the research methods sections. In these cases, the lit review just needs to cover scholarship that is important to the issue you are writing about; sometimes it will also cover key sources that informed your research methodology.

Lit reviews can also be standalone pieces, either as assignments in a class or as publications. In a class, a lit review may be assigned to help students familiarize themselves with a topic and with scholarship in their field, get an idea of the other researchers working on the topic they’re interested in, find gaps in existing research in order to propose new projects, and/or develop a theoretical framework and methodology for later research. As a publication, a lit review usually is meant to help make other scholars’ lives easier by collecting and summarizing, synthesizing, and analyzing existing research on a topic. This can be especially helpful for students or scholars getting into a new research area, or for directing an entire community of scholars toward questions that have not yet been answered.

What are the parts of a lit review?

Most lit reviews use a basic introduction-body-conclusion structure; if your lit review is part of a larger paper, the introduction and conclusion pieces may be just a few sentences while you focus most of your attention on the body. If your lit review is a standalone piece, the introduction and conclusion take up more space and give you a place to discuss your goals, research methods, and conclusions separately from where you discuss the literature itself.

Introduction:

An introductory paragraph that explains what your working topic and thesis is
A forecast of key topics or texts that will appear in the review
Potentially, a description of how you found sources and how you analyzed them for inclusion and discussion in the review (more often found in published, standalone literature reviews than in lit review sections in an article or research paper)
Summarize and synthesize: Give an overview of the main points of each source and combine them into a coherent whole
Analyze and interpret: Don’t just paraphrase other researchers – add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
Critically Evaluate: Mention the strengths and weaknesses of your sources
Write in well-structured paragraphs: Use transition words and topic sentence to draw connections, comparisons, and contrasts.

Conclusion:

Summarize the key findings you have taken from the literature and emphasize their significance
Connect it back to your primary research question

How should I organize my lit review?

Lit reviews can take many different organizational patterns depending on what you are trying to accomplish with the review. Here are some examples:

Chronological : The simplest approach is to trace the development of the topic over time, which helps familiarize the audience with the topic (for instance if you are introducing something that is not commonly known in your field). If you choose this strategy, be careful to avoid simply listing and summarizing sources in order. Try to analyze the patterns, turning points, and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred (as mentioned previously, this may not be appropriate in your discipline — check with a teacher or mentor if you’re unsure).
Thematic : If you have found some recurring central themes that you will continue working with throughout your piece, you can organize your literature review into subsections that address different aspects of the topic. For example, if you are reviewing literature about women and religion, key themes can include the role of women in churches and the religious attitude towards women.
Qualitative versus quantitative research
Empirical versus theoretical scholarship
Divide the research by sociological, historical, or cultural sources
Theoretical : In many humanities articles, the literature review is the foundation for the theoretical framework. You can use it to discuss various theories, models, and definitions of key concepts. You can argue for the relevance of a specific theoretical approach or combine various theorical concepts to create a framework for your research.

What are some strategies or tips I can use while writing my lit review?

Any lit review is only as good as the research it discusses; make sure your sources are well-chosen and your research is thorough. Don’t be afraid to do more research if you discover a new thread as you’re writing. More info on the research process is available in our "Conducting Research" resources .

As you’re doing your research, create an annotated bibliography ( see our page on the this type of document ). Much of the information used in an annotated bibliography can be used also in a literature review, so you’ll be not only partially drafting your lit review as you research, but also developing your sense of the larger conversation going on among scholars, professionals, and any other stakeholders in your topic.

Usually you will need to synthesize research rather than just summarizing it. This means drawing connections between sources to create a picture of the scholarly conversation on a topic over time. Many student writers struggle to synthesize because they feel they don’t have anything to add to the scholars they are citing; here are some strategies to help you:

It often helps to remember that the point of these kinds of syntheses is to show your readers how you understand your research, to help them read the rest of your paper.
Writing teachers often say synthesis is like hosting a dinner party: imagine all your sources are together in a room, discussing your topic. What are they saying to each other?
Look at the in-text citations in each paragraph. Are you citing just one source for each paragraph? This usually indicates summary only. When you have multiple sources cited in a paragraph, you are more likely to be synthesizing them (not always, but often
Read more about synthesis here.

The most interesting literature reviews are often written as arguments (again, as mentioned at the beginning of the page, this is discipline-specific and doesn’t work for all situations). Often, the literature review is where you can establish your research as filling a particular gap or as relevant in a particular way. You have some chance to do this in your introduction in an article, but the literature review section gives a more extended opportunity to establish the conversation in the way you would like your readers to see it. You can choose the intellectual lineage you would like to be part of and whose definitions matter most to your thinking (mostly humanities-specific, but this goes for sciences as well). In addressing these points, you argue for your place in the conversation, which tends to make the lit review more compelling than a simple reporting of other sources.

Get science-backed answers as you write with Paperpal's Research feature

What is a Literature Review? How to Write It (with Examples)

A literature review is a critical analysis and synthesis of existing research on a particular topic. It provides an overview of the current state of knowledge, identifies gaps, and highlights key findings in the literature. 1 The purpose of a literature review is to situate your own research within the context of existing scholarship, demonstrating your understanding of the topic and showing how your work contributes to the ongoing conversation in the field. Learning how to write a literature review is a critical tool for successful research. Your ability to summarize and synthesize prior research pertaining to a certain topic demonstrates your grasp on the topic of study, and assists in the learning process.

What is the purpose of literature review?
a. Habitat Loss and Species Extinction:
b. Range Shifts and Phenological Changes:
c. Ocean Acidification and Coral Reefs:
d. Adaptive Strategies and Conservation Efforts:
How to write a good literature review
Choose a Topic and Define the Research Question:
Decide on the Scope of Your Review:
Select Databases for Searches:
Conduct Searches and Keep Track:
Review the Literature:
Organize and Write Your Literature Review:
Frequently asked questions

What is a literature review?

A well-conducted literature review demonstrates the researcher’s familiarity with the existing literature, establishes the context for their own research, and contributes to scholarly conversations on the topic. One of the purposes of a literature review is also to help researchers avoid duplicating previous work and ensure that their research is informed by and builds upon the existing body of knowledge.

What is the purpose of literature review?

A literature review serves several important purposes within academic and research contexts. Here are some key objectives and functions of a literature review: 2

Contextualizing the Research Problem: The literature review provides a background and context for the research problem under investigation. It helps to situate the study within the existing body of knowledge.
Identifying Gaps in Knowledge: By identifying gaps, contradictions, or areas requiring further research, the researcher can shape the research question and justify the significance of the study. This is crucial for ensuring that the new research contributes something novel to the field.
Understanding Theoretical and Conceptual Frameworks: Literature reviews help researchers gain an understanding of the theoretical and conceptual frameworks used in previous studies. This aids in the development of a theoretical framework for the current research.
Providing Methodological Insights: Another purpose of literature reviews is that it allows researchers to learn about the methodologies employed in previous studies. This can help in choosing appropriate research methods for the current study and avoiding pitfalls that others may have encountered.
Establishing Credibility: A well-conducted literature review demonstrates the researcher’s familiarity with existing scholarship, establishing their credibility and expertise in the field. It also helps in building a solid foundation for the new research.
Informing Hypotheses or Research Questions: The literature review guides the formulation of hypotheses or research questions by highlighting relevant findings and areas of uncertainty in existing literature.

Literature review example

Let’s delve deeper with a literature review example: Let’s say your literature review is about the impact of climate change on biodiversity. You might format your literature review into sections such as the effects of climate change on habitat loss and species extinction, phenological changes, and marine biodiversity. Each section would then summarize and analyze relevant studies in those areas, highlighting key findings and identifying gaps in the research. The review would conclude by emphasizing the need for further research on specific aspects of the relationship between climate change and biodiversity. The following literature review template provides a glimpse into the recommended literature review structure and content, demonstrating how research findings are organized around specific themes within a broader topic.

Literature Review on Climate Change Impacts on Biodiversity:

Climate change is a global phenomenon with far-reaching consequences, including significant impacts on biodiversity. This literature review synthesizes key findings from various studies:

a. Habitat Loss and Species Extinction:

Climate change-induced alterations in temperature and precipitation patterns contribute to habitat loss, affecting numerous species (Thomas et al., 2004). The review discusses how these changes increase the risk of extinction, particularly for species with specific habitat requirements.

b. Range Shifts and Phenological Changes:

Observations of range shifts and changes in the timing of biological events (phenology) are documented in response to changing climatic conditions (Parmesan & Yohe, 2003). These shifts affect ecosystems and may lead to mismatches between species and their resources.

c. Ocean Acidification and Coral Reefs:

The review explores the impact of climate change on marine biodiversity, emphasizing ocean acidification’s threat to coral reefs (Hoegh-Guldberg et al., 2007). Changes in pH levels negatively affect coral calcification, disrupting the delicate balance of marine ecosystems.

d. Adaptive Strategies and Conservation Efforts:

Recognizing the urgency of the situation, the literature review discusses various adaptive strategies adopted by species and conservation efforts aimed at mitigating the impacts of climate change on biodiversity (Hannah et al., 2007). It emphasizes the importance of interdisciplinary approaches for effective conservation planning.

How to write a good literature review

Writing a literature review involves summarizing and synthesizing existing research on a particular topic. A good literature review format should include the following elements.

Introduction: The introduction sets the stage for your literature review, providing context and introducing the main focus of your review.

Opening Statement: Begin with a general statement about the broader topic and its significance in the field.
Scope and Purpose: Clearly define the scope of your literature review. Explain the specific research question or objective you aim to address.
Organizational Framework: Briefly outline the structure of your literature review, indicating how you will categorize and discuss the existing research.
Significance of the Study: Highlight why your literature review is important and how it contributes to the understanding of the chosen topic.
Thesis Statement: Conclude the introduction with a concise thesis statement that outlines the main argument or perspective you will develop in the body of the literature review.

Body: The body of the literature review is where you provide a comprehensive analysis of existing literature, grouping studies based on themes, methodologies, or other relevant criteria.

Organize by Theme or Concept: Group studies that share common themes, concepts, or methodologies. Discuss each theme or concept in detail, summarizing key findings and identifying gaps or areas of disagreement.
Critical Analysis: Evaluate the strengths and weaknesses of each study. Discuss the methodologies used, the quality of evidence, and the overall contribution of each work to the understanding of the topic.
Synthesis of Findings: Synthesize the information from different studies to highlight trends, patterns, or areas of consensus in the literature.
Identification of Gaps: Discuss any gaps or limitations in the existing research and explain how your review contributes to filling these gaps.
Transition between Sections: Provide smooth transitions between different themes or concepts to maintain the flow of your literature review.

Conclusion: The conclusion of your literature review should summarize the main findings, highlight the contributions of the review, and suggest avenues for future research.

Summary of Key Findings: Recap the main findings from the literature and restate how they contribute to your research question or objective.
Contributions to the Field: Discuss the overall contribution of your literature review to the existing knowledge in the field.
Implications and Applications: Explore the practical implications of the findings and suggest how they might impact future research or practice.
Recommendations for Future Research: Identify areas that require further investigation and propose potential directions for future research in the field.
Final Thoughts: Conclude with a final reflection on the importance of your literature review and its relevance to the broader academic community.

Conducting a literature review

Conducting a literature review is an essential step in research that involves reviewing and analyzing existing literature on a specific topic. It’s important to know how to do a literature review effectively, so here are the steps to follow: 1

Choose a Topic and Define the Research Question:

Select a topic that is relevant to your field of study.
Clearly define your research question or objective. Determine what specific aspect of the topic do you want to explore?

Decide on the Scope of Your Review:

Determine the timeframe for your literature review. Are you focusing on recent developments, or do you want a historical overview?
Consider the geographical scope. Is your review global, or are you focusing on a specific region?
Define the inclusion and exclusion criteria. What types of sources will you include? Are there specific types of studies or publications you will exclude?

Select Databases for Searches:

Identify relevant databases for your field. Examples include PubMed, IEEE Xplore, Scopus, Web of Science, and Google Scholar.
Consider searching in library catalogs, institutional repositories, and specialized databases related to your topic.

Conduct Searches and Keep Track:

Develop a systematic search strategy using keywords, Boolean operators (AND, OR, NOT), and other search techniques.
Record and document your search strategy for transparency and replicability.
Keep track of the articles, including publication details, abstracts, and links. Use citation management tools like EndNote, Zotero, or Mendeley to organize your references.

Review the Literature:

Evaluate the relevance and quality of each source. Consider the methodology, sample size, and results of studies.
Organize the literature by themes or key concepts. Identify patterns, trends, and gaps in the existing research.
Summarize key findings and arguments from each source. Compare and contrast different perspectives.
Identify areas where there is a consensus in the literature and where there are conflicting opinions.
Provide critical analysis and synthesis of the literature. What are the strengths and weaknesses of existing research?

Organize and Write Your Literature Review:

Literature review outline should be based on themes, chronological order, or methodological approaches.
Write a clear and coherent narrative that synthesizes the information gathered.
Use proper citations for each source and ensure consistency in your citation style (APA, MLA, Chicago, etc.).
Conclude your literature review by summarizing key findings, identifying gaps, and suggesting areas for future research.

The literature review sample and detailed advice on writing and conducting a review will help you produce a well-structured report. But remember that a literature review is an ongoing process, and it may be necessary to revisit and update it as your research progresses.

Frequently asked questions

A literature review is a critical and comprehensive analysis of existing literature (published and unpublished works) on a specific topic or research question and provides a synthesis of the current state of knowledge in a particular field. A well-conducted literature review is crucial for researchers to build upon existing knowledge, avoid duplication of efforts, and contribute to the advancement of their field. It also helps researchers situate their work within a broader context and facilitates the development of a sound theoretical and conceptual framework for their studies.

Literature review is a crucial component of research writing, providing a solid background for a research paper’s investigation. The aim is to keep professionals up to date by providing an understanding of ongoing developments within a specific field, including research methods, and experimental techniques used in that field, and present that knowledge in the form of a written report. Also, the depth and breadth of the literature review emphasizes the credibility of the scholar in his or her field.

Before writing a literature review, it’s essential to undertake several preparatory steps to ensure that your review is well-researched, organized, and focused. This includes choosing a topic of general interest to you and doing exploratory research on that topic, writing an annotated bibliography, and noting major points, especially those that relate to the position you have taken on the topic.

Literature reviews and academic research papers are essential components of scholarly work but serve different purposes within the academic realm. 3 A literature review aims to provide a foundation for understanding the current state of research on a particular topic, identify gaps or controversies, and lay the groundwork for future research. Therefore, it draws heavily from existing academic sources, including books, journal articles, and other scholarly publications. In contrast, an academic research paper aims to present new knowledge, contribute to the academic discourse, and advance the understanding of a specific research question. Therefore, it involves a mix of existing literature (in the introduction and literature review sections) and original data or findings obtained through research methods.

Literature reviews are essential components of academic and research papers, and various strategies can be employed to conduct them effectively. If you want to know how to write a literature review for a research paper, here are four common approaches that are often used by researchers. Chronological Review: This strategy involves organizing the literature based on the chronological order of publication. It helps to trace the development of a topic over time, showing how ideas, theories, and research have evolved. Thematic Review: Thematic reviews focus on identifying and analyzing themes or topics that cut across different studies. Instead of organizing the literature chronologically, it is grouped by key themes or concepts, allowing for a comprehensive exploration of various aspects of the topic. Methodological Review: This strategy involves organizing the literature based on the research methods employed in different studies. It helps to highlight the strengths and weaknesses of various methodologies and allows the reader to evaluate the reliability and validity of the research findings. Theoretical Review: A theoretical review examines the literature based on the theoretical frameworks used in different studies. This approach helps to identify the key theories that have been applied to the topic and assess their contributions to the understanding of the subject. It’s important to note that these strategies are not mutually exclusive, and a literature review may combine elements of more than one approach. The choice of strategy depends on the research question, the nature of the literature available, and the goals of the review. Additionally, other strategies, such as integrative reviews or systematic reviews, may be employed depending on the specific requirements of the research.

The literature review format can vary depending on the specific publication guidelines. However, there are some common elements and structures that are often followed. Here is a general guideline for the format of a literature review: Introduction: Provide an overview of the topic. Define the scope and purpose of the literature review. State the research question or objective. Body: Organize the literature by themes, concepts, or chronology. Critically analyze and evaluate each source. Discuss the strengths and weaknesses of the studies. Highlight any methodological limitations or biases. Identify patterns, connections, or contradictions in the existing research. Conclusion: Summarize the key points discussed in the literature review. Highlight the research gap. Address the research question or objective stated in the introduction. Highlight the contributions of the review and suggest directions for future research.

Both annotated bibliographies and literature reviews involve the examination of scholarly sources. While annotated bibliographies focus on individual sources with brief annotations, literature reviews provide a more in-depth, integrated, and comprehensive analysis of existing literature on a specific topic. The key differences are as follows:

References

Denney, A. S., & Tewksbury, R. (2013). How to write a literature review.  Journal of criminal justice education ,  24 (2), 218-234.
Pan, M. L. (2016).  Preparing literature reviews: Qualitative and quantitative approaches . Taylor & Francis.
Cantero, C. (2019). How to write a literature review.  San José State University Writing Center .

Paperpal is an AI writing assistant that help academics write better, faster with real-time suggestions for in-depth language and grammar correction. Trained on millions of research manuscripts enhanced by professional academic editors, Paperpal delivers human precision at machine speed.

Try it for free or upgrade to  Paperpal Prime , which unlocks unlimited access to premium features like academic translation, paraphrasing, contextual synonyms, consistency checks and more. It’s like always having a professional academic editor by your side! Go beyond limitations and experience the future of academic writing.  Get Paperpal Prime now at just US$19 a month!

6 Tips for Post-Doc Researchers to Take Their Career to the Next Level

Self-plagiarism in research: what it is and how to avoid it, you may also like, what is hedging in academic writing , how to use ai to enhance your college..., ai + human expertise – a paradigm shift..., how to use paperpal to generate emails &..., ai in education: it’s time to change the..., is it ethical to use ai-generated abstracts without..., do plagiarism checkers detect ai content, word choice problems: how to use the right..., how to avoid plagiarism when using generative ai..., what are journal guidelines on using generative ai....

University of Texas Libraries

Literature Reviews

What is a literature review?
Steps in the Literature Review Process
Define your research question
Determine inclusion and exclusion criteria
Choose databases and search
Review Results
Synthesize Results
Analyze Results
Librarian Support

What is a Literature Review?

A literature or narrative review is a comprehensive review and analysis of the published literature on a specific topic or research question. The literature that is reviewed contains: books, articles, academic articles, conference proceedings, association papers, and dissertations. It contains the most pertinent studies and points to important past and current research and practices. It provides background and context, and shows how your research will contribute to the field.

A literature review should:

Provide a comprehensive and updated review of the literature;
Explain why this review has taken place;
Articulate a position or hypothesis;
Acknowledge and account for conflicting and corroborating points of view

From S age Research Methods

Purpose of a Literature Review

A literature review can be written as an introduction to a study to:

Demonstrate how a study fills a gap in research
Compare a study with other research that's been done

Or it can be a separate work (a research article on its own) which:

Organizes or describes a topic
Describes variables within a particular issue/problem

Limitations of a Literature Review

Some of the limitations of a literature review are:

It's a snapshot in time. Unlike other reviews, this one has beginning, a middle and an end. There may be future developments that could make your work less relevant.
It may be too focused. Some niche studies may miss the bigger picture.
It can be difficult to be comprehensive. There is no way to make sure all the literature on a topic was considered.
It is easy to be biased if you stick to top tier journals. There may be other places where people are publishing exemplary research. Look to open access publications and conferences to reflect a more inclusive collection. Also, make sure to include opposing views (and not just supporting evidence).

Source: Grant, Maria J., and Andrew Booth. “A Typology of Reviews: An Analysis of 14 Review Types and Associated Methodologies.” Health Information & Libraries Journal, vol. 26, no. 2, June 2009, pp. 91–108. Wiley Online Library, doi:10.1111/j.1471-1842.2009.00848.x.

Meryl Brodsky : Communication and Information Studies

Hannah Chapman Tripp : Biology, Neuroscience

Carolyn Cunningham : Human Development & Family Sciences, Psychology, Sociology

Larayne Dallas : Engineering

Janelle Hedstrom : Special Education, Curriculum & Instruction, Ed Leadership & Policy

Susan Macicak : Linguistics

Imelda Vetter : Dell Medical School

For help in other subject areas, please see the guide to library specialists by subject .

Periodically, UT Libraries runs a workshop covering the basics and library support for literature reviews. While we try to offer these once per academic year, we find providing the recording to be helpful to community members who have missed the session. Following is the most recent recording of the workshop, Conducting a Literature Review. To view the recording, a UT login is required.

October 26, 2022 recording
Last Updated: Oct 26, 2022 2:49 PM
URL: https://guides.lib.utexas.edu/literaturereviews

Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, automatically generate references for free.

Knowledge Base
Dissertation
What is a Literature Review? | Guide, Template, & Examples

What is a Literature Review? | Guide, Template, & Examples

Published on 22 February 2022 by Shona McCombes . Revised on 7 June 2022.

There are five key steps to writing a literature review:

Search for relevant literature
Evaluate sources
Identify themes, debates and gaps
Outline the structure
Write your literature review

A good literature review doesn’t just summarise sources – it analyses, synthesises, and critically evaluates to give a clear picture of the state of knowledge on the subject.

Instantly correct all language mistakes in your text

Be assured that you'll submit flawless writing. Upload your document to correct all your mistakes.

Why write a literature review, examples of literature reviews, step 1: search for relevant literature, step 2: evaluate and select sources, step 3: identify themes, debates and gaps, step 4: outline your literature review’s structure, step 5: write your literature review, frequently asked questions about literature reviews, introduction.

Quick Run-through
Step 1 & 2

When you write a dissertation or thesis, you will have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

Demonstrate your familiarity with the topic and scholarly context
Develop a theoretical framework and methodology for your research
Position yourself in relation to other researchers and theorists
Show how your dissertation addresses a gap or contributes to a debate

You might also have to write a literature review as a stand-alone assignment. In this case, the purpose is to evaluate the current state of research and demonstrate your knowledge of scholarly debates around a topic.

The content will look slightly different in each case, but the process of conducting a literature review follows the same steps. We’ve written a step-by-step guide that you can follow below.

The only proofreading tool specialized in correcting academic writing

The academic proofreading tool has been trained on 1000s of academic texts and by native English editors. Making it the most accurate and reliable proofreading tool for students.

Correct my document today

Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research objectives and questions .

If you are writing a literature review as a stand-alone assignment, you will have to choose a focus and develop a central question to direct your search. Unlike a dissertation research question, this question has to be answerable without collecting original data. You should be able to answer it based only on a review of existing publications.

Make a list of keywords

Start by creating a list of keywords related to your research topic. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list if you discover new keywords in the process of your literature search.

Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
Body image, self-perception, self-esteem, mental health
Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some databases to search for journals and articles include:

Your university’s library catalogue
Google Scholar
Project Muse (humanities and social sciences)
Medline (life sciences and biomedicine)
EconLit (economics)
Inspec (physics, engineering and computer science)

You can use boolean operators to help narrow down your search:

Read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

To identify the most important publications on your topic, take note of recurring citations. If the same authors, books or articles keep appearing in your reading, make sure to seek them out.

You probably won’t be able to read absolutely everything that has been written on the topic – you’ll have to evaluate which sources are most relevant to your questions.

For each publication, ask yourself:

What question or problem is the author addressing?
What are the key concepts and how are they defined?
What are the key theories, models and methods? Does the research use established frameworks or take an innovative approach?
What are the results and conclusions of the study?
How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
How does the publication contribute to your understanding of the topic? What are its key insights and arguments?
What are the strengths and weaknesses of the research?

Make sure the sources you use are credible, and make sure you read any landmark studies and major theories in your field of research.

You can find out how many times an article has been cited on Google Scholar – a high citation count means the article has been influential in the field, and should certainly be included in your literature review.

The scope of your review will depend on your topic and discipline: in the sciences you usually only review recent literature, but in the humanities you might take a long historical perspective (for example, to trace how a concept has changed in meaning over time).

Remember that you can use our template to summarise and evaluate sources you’re thinking about using!

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It’s important to keep track of your sources with references to avoid plagiarism . It can be helpful to make an annotated bibliography, where you compile full reference information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

You can use our free APA Reference Generator for quick, correct, consistent citations.

To begin organising your literature review’s argument and structure, you need to understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
Themes: what questions or concepts recur across the literature?
Debates, conflicts and contradictions: where do sources disagree?
Pivotal publications: are there any influential theories or studies that changed the direction of the field?
Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

Most research has focused on young women.
There is an increasing interest in the visual aspects of social media.
But there is still a lack of robust research on highly-visual platforms like Instagram and Snapchat – this is a gap that you could address in your own research.

There are various approaches to organising the body of a literature review. You should have a rough idea of your strategy before you start writing.

Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarising sources in order.

Try to analyse patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organise your literature review into subsections that address different aspects of the topic.

Methodological

Look at what results have emerged in qualitative versus quantitative research
Discuss how the topic has been approached by empirical versus theoretical scholarship
Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text, your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

If you are writing the literature review as part of your dissertation or thesis, reiterate your central problem or research question and give a brief summary of the scholarly context. You can emphasise the timeliness of the topic (“many recent studies have focused on the problem of x”) or highlight a gap in the literature (“while there has been much research on x, few researchers have taken y into consideration”).

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, make sure to follow these tips:

Summarise and synthesise: give an overview of the main points of each source and combine them into a coherent whole.
Analyse and interpret: don’t just paraphrase other researchers – add your own interpretations, discussing the significance of findings in relation to the literature as a whole.
Critically evaluate: mention the strengths and weaknesses of your sources.
Write in well-structured paragraphs: use transitions and topic sentences to draw connections, comparisons and contrasts.

In the conclusion, you should summarise the key findings you have taken from the literature and emphasise their significance.

If the literature review is part of your dissertation or thesis, reiterate how your research addresses gaps and contributes new knowledge, or discuss how you have drawn on existing theories and methods to build a framework for your research. This can lead directly into your methodology section.

A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a dissertation , thesis, research paper , or proposal .

There are several reasons to conduct a literature review at the beginning of a research project:

To familiarise yourself with the current state of knowledge on your topic
To ensure that you’re not just repeating what others have already done
To identify gaps in knowledge and unresolved problems that your research can address
To develop your theoretical framework and methodology
To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the ‘Cite this Scribbr article’ button to automatically add the citation to our free Reference Generator.

McCombes, S. (2022, June 07). What is a Literature Review? | Guide, Template, & Examples. Scribbr. Retrieved 9 April 2024, from https://www.scribbr.co.uk/thesis-dissertation/literature-review/

Is this article helpful?

Shona McCombes

Other students also liked, how to write a dissertation proposal | a step-by-step guide, what is a theoretical framework | a step-by-step guide, what is a research methodology | steps & tips.

Reference management. Clean and simple.

What is a literature review? [with examples]

What is a literature review?

The purpose of a literature review, how to write a literature review, the format of a literature review, general formatting rules, the length of a literature review, literature review examples, frequently asked questions about literature reviews, related articles.

A literature review is an assessment of the sources in a chosen topic of research.

In a literature review, you’re expected to report on the existing scholarly conversation, without adding new contributions.

If you are currently writing one, you've come to the right place. In the following paragraphs, we will explain:

the objective of a literature review
how to write a literature review
the basic format of a literature review

Tip: It’s not always mandatory to add a literature review in a paper. Theses and dissertations often include them, whereas research papers may not. Make sure to consult with your instructor for exact requirements.

The four main objectives of a literature review are:

Studying the references of your research area
Summarizing the main arguments
Identifying current gaps, stances, and issues
Presenting all of the above in a text

Ultimately, the main goal of a literature review is to provide the researcher with sufficient knowledge about the topic in question so that they can eventually make an intervention.

The format of a literature review is fairly standard. It includes an:

introduction that briefly introduces the main topic
body that includes the main discussion of the key arguments
conclusion that highlights the gaps and issues of the literature

➡️ Take a look at our guide on how to write a literature review to learn more about how to structure a literature review.

First of all, a literature review should have its own labeled section. You should indicate clearly in the table of contents where the literature can be found, and you should label this section as “Literature Review.”

➡️ For more information on writing a thesis, visit our guide on how to structure a thesis .

There is no set amount of words for a literature review, so the length depends on the research. If you are working with a large amount of sources, it will be long. If your paper does not depend entirely on references, it will be short.

Take a look at these three theses featuring great literature reviews:

School-Based Speech-Language Pathologist's Perceptions of Sensory Food Aversions in Children [ PDF , see page 20]
Who's Writing What We Read: Authorship in Criminological Research [ PDF , see page 4]
A Phenomenological Study of the Lived Experience of Online Instructors of Theological Reflection at Christian Institutions Accredited by the Association of Theological Schools [ PDF , see page 56]

Literature reviews are most commonly found in theses and dissertations. However, you find them in research papers as well.

There is no set amount of words for a literature review, so the length depends on the research. If you are working with a large amount of sources, then it will be long. If your paper does not depend entirely on references, then it will be short.

No. A literature review should have its own independent section. You should indicate clearly in the table of contents where the literature review can be found, and label this section as “Literature Review.”

The main goal of a literature review is to provide the researcher with sufficient knowledge about the topic in question so that they can eventually make an intervention.

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

View all journals
Explore content
About the journal
Publish with us
Sign up for alerts
CAREER FEATURE
04 December 2020
Correction 09 December 2020

How to write a superb literature review

Andy Tay is a freelance writer based in Singapore.

You can also search for this author in PubMed Google Scholar

Literature reviews are important resources for scientists. They provide historical context for a field while offering opinions on its future trajectory. Creating them can provide inspiration for one’s own research, as well as some practice in writing. But few scientists are trained in how to write a review — or in what constitutes an excellent one. Even picking the appropriate software to use can be an involved decision (see ‘Tools and techniques’). So Nature asked editors and working scientists with well-cited reviews for their tips.

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 51 print issues and online access

185,98 € per year

only 3,65 € per issue

Rent or buy this article

Prices vary by article type

Prices may be subject to local taxes which are calculated during checkout

doi: https://doi.org/10.1038/d41586-020-03422-x

Interviews have been edited for length and clarity.

Updates & Corrections

Correction 09 December 2020 : An earlier version of the tables in this article included some incorrect details about the programs Zotero, Endnote and Manubot. These have now been corrected.

Hsing, I.-M., Xu, Y. & Zhao, W. Electroanalysis 19 , 755–768 (2007).

Article Google Scholar

Ledesma, H. A. et al. Nature Nanotechnol. 14 , 645–657 (2019).

Article PubMed Google Scholar

Brahlek, M., Koirala, N., Bansal, N. & Oh, S. Solid State Commun. 215–216 , 54–62 (2015).

Choi, Y. & Lee, S. Y. Nature Rev. Chem . https://doi.org/10.1038/s41570-020-00221-w (2020).

Download references

Research management

How I harnessed media engagement to supercharge my research career

Career Column 09 APR 24

How we landed job interviews for professorships straight out of our PhD programmes

Career Column 08 APR 24

Three ways ChatGPT helps me in my academic writing

How two PhD students overcame the odds to snag tenure-track jobs

Adopt universal standards for study adaptation to boost health, education and social-science research

Correspondence 02 APR 24

Is ChatGPT corrupting peer review? Telltale words hint at AI use

News 10 APR 24

Rwanda 30 years on: understanding the horror of genocide

Editorial 09 APR 24

Junior Group Leader Position at IMBA - Institute of Molecular Biotechnology

The Institute of Molecular Biotechnology (IMBA) is one of Europe’s leading institutes for basic research in the life sciences. IMBA is located on t...

Austria (AT)

IMBA - Institute of Molecular Biotechnology

Open Rank Faculty, Center for Public Health Genomics

Center for Public Health Genomics & UVA Comprehensive Cancer Center seek 2 tenure-track faculty members in Cancer Precision Medicine/Precision Health.

Charlottesville, Virginia

Center for Public Health Genomics at the University of Virginia

Husbandry Technician I

Memphis, Tennessee

St. Jude Children's Research Hospital (St. Jude)

Lead Researcher – Department of Bone Marrow Transplantation & Cellular Therapy

Researcher in the center for in vivo imaging and therapy.

Quick links

Explore articles by subject
Guide to authors
Editorial policies

Libraries | Research Guides

Literature reviews, what is a literature review, learning more about how to do a literature review.

Planning the Review
The Research Question
Choosing Where to Search
Organizing the Review
Writing the Review

A literature review is a review and synthesis of existing research on a topic or research question. A literature review is meant to analyze the scholarly literature, make connections across writings and identify strengths, weaknesses, trends, and missing conversations. A literature review should address different aspects of a topic as it relates to your research question. A literature review goes beyond a description or summary of the literature you have read.

Sage Research Methods Core Collection This link opens in a new window SAGE Research Methods supports research at all levels by providing material to guide users through every step of the research process. SAGE Research Methods is the ultimate methods library with more than 1000 books, reference works, journal articles, and instructional videos by world-leading academics from across the social sciences, including the largest collection of qualitative methods books available online from any scholarly publisher. – Publisher

Next: Planning the Review >>
Last Updated: Jan 17, 2024 10:05 AM
URL: https://libguides.northwestern.edu/literaturereviews

UConn Library
Literature Review: The What, Why and How-to Guide
Introduction

Literature Review: The What, Why and How-to Guide — Introduction

Getting Started
How to Pick a Topic
Strategies to Find Sources
Evaluating Sources & Lit. Reviews
Tips for Writing Literature Reviews
Writing Literature Review: Useful Sites
Citation Resources
Other Academic Writings

What are Literature Reviews?

So, what is a literature review? "A literature review is an account of what has been published on a topic by accredited scholars and researchers. In writing the literature review, your purpose is to convey to your reader what knowledge and ideas have been established on a topic, and what their strengths and weaknesses are. As a piece of writing, the literature review must be defined by a guiding concept (e.g., your research objective, the problem or issue you are discussing, or your argumentative thesis). It is not just a descriptive list of the material available, or a set of summaries." Taylor, D. The literature review: A few tips on conducting it . University of Toronto Health Sciences Writing Centre.

Goals of Literature Reviews

What are the goals of creating a Literature Review? A literature could be written to accomplish different aims:

To develop a theory or evaluate an existing theory
To summarize the historical or existing state of a research topic
Identify a problem in a field of research

Baumeister, R. F., & Leary, M. R. (1997). Writing narrative literature reviews . Review of General Psychology , 1 (3), 311-320.

What kinds of sources require a Literature Review?

A research paper assigned in a course
A thesis or dissertation
A grant proposal
An article intended for publication in a journal

All these instances require you to collect what has been written about your research topic so that you can demonstrate how your own research sheds new light on the topic.

Types of Literature Reviews

What kinds of literature reviews are written?

Narrative review: The purpose of this type of review is to describe the current state of the research on a specific topic/research and to offer a critical analysis of the literature reviewed. Studies are grouped by research/theoretical categories, and themes and trends, strengths and weakness, and gaps are identified. The review ends with a conclusion section which summarizes the findings regarding the state of the research of the specific study, the gaps identify and if applicable, explains how the author's research will address gaps identify in the review and expand the knowledge on the topic reviewed.

Example : Predictors and Outcomes of U.S. Quality Maternity Leave: A Review and Conceptual Framework: 10.1177/08948453211037398

Systematic review : "The authors of a systematic review use a specific procedure to search the research literature, select the studies to include in their review, and critically evaluate the studies they find." (p. 139). Nelson, L. K. (2013). Research in Communication Sciences and Disorders . Plural Publishing.

Example : The effect of leave policies on increasing fertility: a systematic review: 10.1057/s41599-022-01270-w

Meta-analysis : "Meta-analysis is a method of reviewing research findings in a quantitative fashion by transforming the data from individual studies into what is called an effect size and then pooling and analyzing this information. The basic goal in meta-analysis is to explain why different outcomes have occurred in different studies." (p. 197). Roberts, M. C., & Ilardi, S. S. (2003). Handbook of Research Methods in Clinical Psychology . Blackwell Publishing.

Example : Employment Instability and Fertility in Europe: A Meta-Analysis: 10.1215/00703370-9164737

Meta-synthesis : "Qualitative meta-synthesis is a type of qualitative study that uses as data the findings from other qualitative studies linked by the same or related topic." (p.312). Zimmer, L. (2006). Qualitative meta-synthesis: A question of dialoguing with texts . Journal of Advanced Nursing , 53 (3), 311-318.

Example : Women’s perspectives on career successes and barriers: A qualitative meta-synthesis: 10.1177/05390184221113735

Literature Reviews in the Health Sciences

UConn Health subject guide on systematic reviews Explanation of the different review types used in health sciences literature as well as tools to help you find the right review type
<< Previous: Getting Started
Next: How to Pick a Topic >>
Last Updated: Sep 21, 2022 2:16 PM
URL: https://guides.lib.uconn.edu/literaturereview

Harvey Cushing/John Hay Whitney Medical Library

Collections
Research Help

YSN Doctoral Programs: Steps in Conducting a Literature Review

Biomedical Databases
Global (Public Health) Databases
Soc. Sci., History, and Law Databases
Grey Literature
Trials Registers
Data and Statistics
Public Policy
Google Tips
Recommended Books
Steps in Conducting a Literature Review

What is a literature review?

A literature review is an integrated analysis -- not just a summary-- of scholarly writings and other relevant evidence related directly to your research question. That is, it represents a synthesis of the evidence that provides background information on your topic and shows a association between the evidence and your research question.

A literature review may be a stand alone work or the introduction to a larger research paper, depending on the assignment. Rely heavily on the guidelines your instructor has given you.

Why is it important?

A literature review is important because it:

Explains the background of research on a topic.
Demonstrates why a topic is significant to a subject area.
Discovers relationships between research studies/ideas.
Identifies major themes, concepts, and researchers on a topic.
Identifies critical gaps and points of disagreement.
Discusses further research questions that logically come out of the previous studies.

APA7 Style resources

APA Style Blog - for those harder to find answers

1. Choose a topic. Define your research question.

Your literature review should be guided by your central research question. The literature represents background and research developments related to a specific research question, interpreted and analyzed by you in a synthesized way.

Make sure your research question is not too broad or too narrow. Is it manageable?
Begin writing down terms that are related to your question. These will be useful for searches later.
If you have the opportunity, discuss your topic with your professor and your class mates.

2. Decide on the scope of your review

How many studies do you need to look at? How comprehensive should it be? How many years should it cover?

This may depend on your assignment. How many sources does the assignment require?

3. Select the databases you will use to conduct your searches.

Make a list of the databases you will search.

Where to find databases:

use the tabs on this guide
Find other databases in the Nursing Information Resources web page
More on the Medical Library web page
... and more on the Yale University Library web page

4. Conduct your searches to find the evidence. Keep track of your searches.

Use the key words in your question, as well as synonyms for those words, as terms in your search. Use the database tutorials for help.
Save the searches in the databases. This saves time when you want to redo, or modify, the searches. It is also helpful to use as a guide is the searches are not finding any useful results.
Review the abstracts of research studies carefully. This will save you time.
Use the bibliographies and references of research studies you find to locate others.
Check with your professor, or a subject expert in the field, if you are missing any key works in the field.
Ask your librarian for help at any time.
Use a citation manager, such as EndNote as the repository for your citations. See the EndNote tutorials for help.

Review the literature

Some questions to help you analyze the research:

What was the research question of the study you are reviewing? What were the authors trying to discover?
Was the research funded by a source that could influence the findings?
What were the research methodologies? Analyze its literature review, the samples and variables used, the results, and the conclusions.
Does the research seem to be complete? Could it have been conducted more soundly? What further questions does it raise?
If there are conflicting studies, why do you think that is?
How are the authors viewed in the field? Has this study been cited? If so, how has it been analyzed?

Tips:

Review the abstracts carefully.
Keep careful notes so that you may track your thought processes during the research process.
Create a matrix of the studies for easy analysis, and synthesis, across all of the studies.
<< Previous: Recommended Books
Last Updated: Jan 4, 2024 10:52 AM
URL: https://guides.library.yale.edu/YSNDoctoral

How To Write An A-Grade Literature Review

3 straightforward steps (with examples) + free template.

By: Derek Jansen (MBA) | Expert Reviewed By: Dr. Eunice Rautenbach | October 2019

Quality research is about building onto the existing work of others , “standing on the shoulders of giants”, as Newton put it. The literature review chapter of your dissertation, thesis or research project is where you synthesise this prior work and lay the theoretical foundation for your own research.

Long story short, this chapter is a pretty big deal, which is why you want to make sure you get it right . In this post, I’ll show you exactly how to write a literature review in three straightforward steps, so you can conquer this vital chapter (the smart way).

Overview: The Literature Review Process

Understanding the “ why “
Finding the relevant literature
Cataloguing and synthesising the information
Outlining & writing up your literature review
Example of a literature review

But first, the “why”…

Before we unpack how to write the literature review chapter, we’ve got to look at the why . To put it bluntly, if you don’t understand the function and purpose of the literature review process, there’s no way you can pull it off well. So, what exactly is the purpose of the literature review?

Well, there are (at least) four core functions:

For you to gain an understanding (and demonstrate this understanding) of where the research is at currently, what the key arguments and disagreements are.
For you to identify the gap(s) in the literature and then use this as justification for your own research topic.
To help you build a conceptual framework for empirical testing (if applicable to your research topic).
To inform your methodological choices and help you source tried and tested questionnaires (for interviews ) and measurement instruments (for surveys ).

Most students understand the first point but don’t give any thought to the rest. To get the most from the literature review process, you must keep all four points front of mind as you review the literature (more on this shortly), or you’ll land up with a wonky foundation.

Okay – with the why out the way, let’s move on to the how . As mentioned above, writing your literature review is a process, which I’ll break down into three steps:

Finding the most suitable literature
Understanding , distilling and organising the literature
Planning and writing up your literature review chapter

Importantly, you must complete steps one and two before you start writing up your chapter. I know it’s very tempting, but don’t try to kill two birds with one stone and write as you read. You’ll invariably end up wasting huge amounts of time re-writing and re-shaping, or you’ll just land up with a disjointed, hard-to-digest mess . Instead, you need to read first and distil the information, then plan and execute the writing.

Step 1: Find the relevant literature

Naturally, the first step in the literature review journey is to hunt down the existing research that’s relevant to your topic. While you probably already have a decent base of this from your research proposal , you need to expand on this substantially in the dissertation or thesis itself.

Essentially, you need to be looking for any existing literature that potentially helps you answer your research question (or develop it, if that’s not yet pinned down). There are numerous ways to find relevant literature, but I’ll cover my top four tactics here. I’d suggest combining all four methods to ensure that nothing slips past you:

Method 1 – Google Scholar Scrubbing

Google’s academic search engine, Google Scholar , is a great starting point as it provides a good high-level view of the relevant journal articles for whatever keyword you throw at it. Most valuably, it tells you how many times each article has been cited, which gives you an idea of how credible (or at least, popular) it is. Some articles will be free to access, while others will require an account, which brings us to the next method.

Method 2 – University Database Scrounging

Generally, universities provide students with access to an online library, which provides access to many (but not all) of the major journals.

So, if you find an article using Google Scholar that requires paid access (which is quite likely), search for that article in your university’s database – if it’s listed there, you’ll have access. Note that, generally, the search engine capabilities of these databases are poor, so make sure you search for the exact article name, or you might not find it.

Method 3 – Journal Article Snowballing

At the end of every academic journal article, you’ll find a list of references. As with any academic writing, these references are the building blocks of the article, so if the article is relevant to your topic, there’s a good chance a portion of the referenced works will be too. Do a quick scan of the titles and see what seems relevant, then search for the relevant ones in your university’s database.

Method 4 – Dissertation Scavenging

Similar to Method 3 above, you can leverage other students’ dissertations. All you have to do is skim through literature review chapters of existing dissertations related to your topic and you’ll find a gold mine of potential literature. Usually, your university will provide you with access to previous students’ dissertations, but you can also find a much larger selection in the following databases:

Open Access Theses & Dissertations
Stanford SearchWorks

Keep in mind that dissertations and theses are not as academically sound as published, peer-reviewed journal articles (because they’re written by students, not professionals), so be sure to check the credibility of any sources you find using this method. You can do this by assessing the citation count of any given article in Google Scholar. If you need help with assessing the credibility of any article, or with finding relevant research in general, you can chat with one of our Research Specialists .

Alright – with a good base of literature firmly under your belt, it’s time to move onto the next step.

Need a helping hand?

Step 2: Log, catalogue and synthesise

Once you’ve built a little treasure trove of articles, it’s time to get reading and start digesting the information – what does it all mean?

While I present steps one and two (hunting and digesting) as sequential, in reality, it’s more of a back-and-forth tango – you’ll read a little , then have an idea, spot a new citation, or a new potential variable, and then go back to searching for articles. This is perfectly natural – through the reading process, your thoughts will develop , new avenues might crop up, and directional adjustments might arise. This is, after all, one of the main purposes of the literature review process (i.e. to familiarise yourself with the current state of research in your field).

As you’re working through your treasure chest, it’s essential that you simultaneously start organising the information. There are three aspects to this:

Logging reference information
Building an organised catalogue
Distilling and synthesising the information

I’ll discuss each of these below:

2.1 – Log the reference information

As you read each article, you should add it to your reference management software. I usually recommend Mendeley for this purpose (see the Mendeley 101 video below), but you can use whichever software you’re comfortable with. Most importantly, make sure you load EVERY article you read into your reference manager, even if it doesn’t seem very relevant at the time.

2.2 – Build an organised catalogue

In the beginning, you might feel confident that you can remember who said what, where, and what their main arguments were. Trust me, you won’t. If you do a thorough review of the relevant literature (as you must!), you’re going to read many, many articles, and it’s simply impossible to remember who said what, when, and in what context . Also, without the bird’s eye view that a catalogue provides, you’ll miss connections between various articles, and have no view of how the research developed over time. Simply put, it’s essential to build your own catalogue of the literature.

I would suggest using Excel to build your catalogue, as it allows you to run filters, colour code and sort – all very useful when your list grows large (which it will). How you lay your spreadsheet out is up to you, but I’d suggest you have the following columns (at minimum):

Author, date, title – Start with three columns containing this core information. This will make it easy for you to search for titles with certain words, order research by date, or group by author.
Categories or keywords – You can either create multiple columns, one for each category/theme and then tick the relevant categories, or you can have one column with keywords.
Key arguments/points – Use this column to succinctly convey the essence of the article, the key arguments and implications thereof for your research.
Context – Note the socioeconomic context in which the research was undertaken. For example, US-based, respondents aged 25-35, lower- income, etc. This will be useful for making an argument about gaps in the research.
Methodology – Note which methodology was used and why. Also, note any issues you feel arise due to the methodology. Again, you can use this to make an argument about gaps in the research.
Quotations – Note down any quoteworthy lines you feel might be useful later.
Notes – Make notes about anything not already covered. For example, linkages to or disagreements with other theories, questions raised but unanswered, shortcomings or limitations, and so forth.

If you’d like, you can try out our free catalog template here (see screenshot below).

2.3 – Digest and synthesise

Most importantly, as you work through the literature and build your catalogue, you need to synthesise all the information in your own mind – how does it all fit together? Look for links between the various articles and try to develop a bigger picture view of the state of the research. Some important questions to ask yourself are:

What answers does the existing research provide to my own research questions ?
Which points do the researchers agree (and disagree) on?
How has the research developed over time?
Where do the gaps in the current research lie?

To help you develop a big-picture view and synthesise all the information, you might find mind mapping software such as Freemind useful. Alternatively, if you’re a fan of physical note-taking, investing in a large whiteboard might work for you.

Mind mapping is a useful way to plan your literature review.

Step 3: Outline and write it up!

Once you’re satisfied that you have digested and distilled all the relevant literature in your mind, it’s time to put pen to paper (or rather, fingers to keyboard). There are two steps here – outlining and writing:

3.1 – Draw up your outline

Having spent so much time reading, it might be tempting to just start writing up without a clear structure in mind. However, it’s critically important to decide on your structure and develop a detailed outline before you write anything. Your literature review chapter needs to present a clear, logical and an easy to follow narrative – and that requires some planning. Don’t try to wing it!

Naturally, you won’t always follow the plan to the letter, but without a detailed outline, you’re more than likely going to end up with a disjointed pile of waffle , and then you’re going to spend a far greater amount of time re-writing, hacking and patching. The adage, “measure twice, cut once” is very suitable here.

In terms of structure, the first decision you’ll have to make is whether you’ll lay out your review thematically (into themes) or chronologically (by date/period). The right choice depends on your topic, research objectives and research questions, which we discuss in this article .

Once that’s decided, you need to draw up an outline of your entire chapter in bullet point format. Try to get as detailed as possible, so that you know exactly what you’ll cover where, how each section will connect to the next, and how your entire argument will develop throughout the chapter. Also, at this stage, it’s a good idea to allocate rough word count limits for each section, so that you can identify word count problems before you’ve spent weeks or months writing!

PS – check out our free literature review chapter template…

3.2 – Get writing

With a detailed outline at your side, it’s time to start writing up (finally!). At this stage, it’s common to feel a bit of writer’s block and find yourself procrastinating under the pressure of finally having to put something on paper. To help with this, remember that the objective of the first draft is not perfection – it’s simply to get your thoughts out of your head and onto paper, after which you can refine them. The structure might change a little, the word count allocations might shift and shuffle, and you might add or remove a section – that’s all okay. Don’t worry about all this on your first draft – just get your thoughts down on paper.

Once you’ve got a full first draft (however rough it may be), step away from it for a day or two (longer if you can) and then come back at it with fresh eyes. Pay particular attention to the flow and narrative – does it fall fit together and flow from one section to another smoothly? Now’s the time to try to improve the linkage from each section to the next, tighten up the writing to be more concise, trim down word count and sand it down into a more digestible read.

Once you’ve done that, give your writing to a friend or colleague who is not a subject matter expert and ask them if they understand the overall discussion. The best way to assess this is to ask them to explain the chapter back to you. This technique will give you a strong indication of which points were clearly communicated and which weren’t. If you’re working with Grad Coach, this is a good time to have your Research Specialist review your chapter.

Finally, tighten it up and send it off to your supervisor for comment. Some might argue that you should be sending your work to your supervisor sooner than this (indeed your university might formally require this), but in my experience, supervisors are extremely short on time (and often patience), so, the more refined your chapter is, the less time they’ll waste on addressing basic issues (which you know about already) and the more time they’ll spend on valuable feedback that will increase your mark-earning potential.

Literature Review Example

In the video below, we unpack an actual literature review so that you can see how all the core components come together in reality.

Let’s Recap

In this post, we’ve covered how to research and write up a high-quality literature review chapter. Let’s do a quick recap of the key takeaways:

It is essential to understand the WHY of the literature review before you read or write anything. Make sure you understand the 4 core functions of the process.
The first step is to hunt down the relevant literature . You can do this using Google Scholar, your university database, the snowballing technique and by reviewing other dissertations and theses.
Next, you need to log all the articles in your reference manager , build your own catalogue of literature and synthesise all the research.
Following that, you need to develop a detailed outline of your entire chapter – the more detail the better. Don’t start writing without a clear outline (on paper, not in your head!)
Write up your first draft in rough form – don’t aim for perfection. Remember, done beats perfect.
Refine your second draft and get a layman’s perspective on it . Then tighten it up and submit it to your supervisor.

Psst… there’s more!

This post is an extract from our bestselling Udemy Course, Literature Review Bootcamp . If you want to work smart, you don't want to miss this .

You Might Also Like:

38 Comments

Thank you very much. This page is an eye opener and easy to comprehend.

This is awesome!

I wish I come across GradCoach earlier enough.

But all the same I’ll make use of this opportunity to the fullest.

Thank you for this good job.

Keep it up!

You’re welcome, Yinka. Thank you for the kind words. All the best writing your literature review.

Thank you for a very useful literature review session. Although I am doing most of the steps…it being my first masters an Mphil is a self study and one not sure you are on the right track. I have an amazing supervisor but one also knows they are super busy. So not wanting to bother on the minutae. Thank you.

You’re most welcome, Renee. Good luck with your literature review 🙂

This has been really helpful. Will make full use of it. 🙂

Thank you Gradcoach.

Really agreed. Admirable effort

thank you for this beautiful well explained recap.

Thank you so much for your guide of video and other instructions for the dissertation writing.

It is instrumental. It encouraged me to write a dissertation now.

Thank you the video was great – from someone that knows nothing thankyou

an amazing and very constructive way of presetting a topic, very useful, thanks for the effort,

It is timely

It is very good video of guidance for writing a research proposal and a dissertation. Since I have been watching and reading instructions, I have started my research proposal to write. I appreciate to Mr Jansen hugely.

I learn a lot from your videos. Very comprehensive and detailed.

Thank you for sharing your knowledge. As a research student, you learn better with your learning tips in research

I was really stuck in reading and gathering information but after watching these things are cleared thanks, it is so helpful.

Really helpful, Thank you for the effort in showing such information

This is super helpful thank you very much.

Thank you for this whole literature writing review.You have simplified the process.

I’m so glad I found GradCoach. Excellent information, Clear explanation, and Easy to follow, Many thanks Derek!

You’re welcome, Maithe. Good luck writing your literature review 🙂

Thank you Coach, you have greatly enriched and improved my knowledge

Great piece, so enriching and it is going to help me a great lot in my project and thesis, thanks so much

This is THE BEST site for ANYONE doing a masters or doctorate! Thank you for the sound advice and templates. You rock!

Thanks, Stephanie 🙂

This is mind blowing, the detailed explanation and simplicity is perfect.

I am doing two papers on my final year thesis, and I must stay I feel very confident to face both headlong after reading this article.

thank you so much.

if anyone is to get a paper done on time and in the best way possible, GRADCOACH is certainly the go to area!

This is very good video which is well explained with detailed explanation

Thank you excellent piece of work and great mentoring

Thanks, it was useful

Thank you very much. the video and the information were very helpful.

Good morning scholar. I’m delighted coming to know you even before the commencement of my dissertation which hopefully is expected in not more than six months from now. I would love to engage my study under your guidance from the beginning to the end. I love to know how to do good job

Thank you so much Derek for such useful information on writing up a good literature review. I am at a stage where I need to start writing my one. My proposal was accepted late last year but I honestly did not know where to start

Like the name of your YouTube implies you are GRAD (great,resource person, about dissertation). In short you are smart enough in coaching research work.

This is a very well thought out webpage. Very informative and a great read.

Very timely.

I appreciate.

Very comprehensive and eye opener for me as beginner in postgraduate study. Well explained and easy to understand. Appreciate and good reference in guiding me in my research journey. Thank you

Thank you. I requested to download the free literature review template, however, your website wouldn’t allow me to complete the request or complete a download. May I request that you email me the free template? Thank you.

Submit a Comment Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Print Friendly

USC Libraries
Research Guides

Organizing Your Social Sciences Research Paper

5. The Literature Review
Purpose of Guide
Design Flaws to Avoid
Independent and Dependent Variables
Glossary of Research Terms
Reading Research Effectively
Narrowing a Topic Idea
Broadening a Topic Idea
Extending the Timeliness of a Topic Idea
Academic Writing Style
Applying Critical Thinking
Choosing a Title
Making an Outline
Paragraph Development
Research Process Video Series
Executive Summary
The C.A.R.S. Model
Background Information
The Research Problem/Question
Theoretical Framework
Citation Tracking
Content Alert Services
Evaluating Sources
Primary Sources
Secondary Sources
Tiertiary Sources
Scholarly vs. Popular Publications
Qualitative Methods
Quantitative Methods
Insiderness
Using Non-Textual Elements
Limitations of the Study
Common Grammar Mistakes
Writing Concisely
Avoiding Plagiarism
Footnotes or Endnotes?
Further Readings
Generative AI and Writing
USC Libraries Tutorials and Other Guides
Bibliography

A literature review surveys prior research published in books, scholarly articles, and any other sources relevant to a particular issue, area of research, or theory, and by so doing, provides a description, summary, and critical evaluation of these works in relation to the research problem being investigated. Literature reviews are designed to provide an overview of sources you have used in researching a particular topic and to demonstrate to your readers how your research fits within existing scholarship about the topic.

Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . Fourth edition. Thousand Oaks, CA: SAGE, 2014.

Importance of a Good Literature Review

A literature review may consist of simply a summary of key sources, but in the social sciences, a literature review usually has an organizational pattern and combines both summary and synthesis, often within specific conceptual categories . A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information in a way that informs how you are planning to investigate a research problem. The analytical features of a literature review might:

Give a new interpretation of old material or combine new with old interpretations,
Trace the intellectual progression of the field, including major debates,
Depending on the situation, evaluate the sources and advise the reader on the most pertinent or relevant research, or
Usually in the conclusion of a literature review, identify where gaps exist in how a problem has been researched to date.

Given this, the purpose of a literature review is to:

Place each work in the context of its contribution to understanding the research problem being studied.
Describe the relationship of each work to the others under consideration.
Identify new ways to interpret prior research.
Reveal any gaps that exist in the literature.
Resolve conflicts amongst seemingly contradictory previous studies.
Identify areas of prior scholarship to prevent duplication of effort.
Point the way in fulfilling a need for additional research.
Locate your own research within the context of existing literature [very important].

Types of Literature Reviews

It is important to think of knowledge in a given field as consisting of three layers. First, there are the primary studies that researchers conduct and publish. Second are the reviews of those studies that summarize and offer new interpretations built from and often extending beyond the primary studies. Third, there are the perceptions, conclusions, opinion, and interpretations that are shared informally among scholars that become part of the body of epistemological traditions within the field.

In composing a literature review, it is important to note that it is often this third layer of knowledge that is cited as "true" even though it often has only a loose relationship to the primary studies and secondary literature reviews. Given this, while literature reviews are designed to provide an overview and synthesis of pertinent sources you have explored, there are a number of approaches you could adopt depending upon the type of analysis underpinning your study.

Argumentative Review This form examines literature selectively in order to support or refute an argument, deeply embedded assumption, or philosophical problem already established in the literature. The purpose is to develop a body of literature that establishes a contrarian viewpoint. Given the value-laden nature of some social science research [e.g., educational reform; immigration control], argumentative approaches to analyzing the literature can be a legitimate and important form of discourse. However, note that they can also introduce problems of bias when they are used to make summary claims of the sort found in systematic reviews [see below].

Integrative Review Considered a form of research that reviews, critiques, and synthesizes representative literature on a topic in an integrated way such that new frameworks and perspectives on the topic are generated. The body of literature includes all studies that address related or identical hypotheses or research problems. A well-done integrative review meets the same standards as primary research in regard to clarity, rigor, and replication. This is the most common form of review in the social sciences.

Historical Review Few things rest in isolation from historical precedent. Historical literature reviews focus on examining research throughout a period of time, often starting with the first time an issue, concept, theory, phenomena emerged in the literature, then tracing its evolution within the scholarship of a discipline. The purpose is to place research in a historical context to show familiarity with state-of-the-art developments and to identify the likely directions for future research.

Methodological Review A review does not always focus on what someone said [findings], but how they came about saying what they say [method of analysis]. Reviewing methods of analysis provides a framework of understanding at different levels [i.e. those of theory, substantive fields, research approaches, and data collection and analysis techniques], how researchers draw upon a wide variety of knowledge ranging from the conceptual level to practical documents for use in fieldwork in the areas of ontological and epistemological consideration, quantitative and qualitative integration, sampling, interviewing, data collection, and data analysis. This approach helps highlight ethical issues which you should be aware of and consider as you go through your own study.

Systematic Review This form consists of an overview of existing evidence pertinent to a clearly formulated research question, which uses pre-specified and standardized methods to identify and critically appraise relevant research, and to collect, report, and analyze data from the studies that are included in the review. The goal is to deliberately document, critically evaluate, and summarize scientifically all of the research about a clearly defined research problem . Typically it focuses on a very specific empirical question, often posed in a cause-and-effect form, such as "To what extent does A contribute to B?" This type of literature review is primarily applied to examining prior research studies in clinical medicine and allied health fields, but it is increasingly being used in the social sciences.

Theoretical Review The purpose of this form is to examine the corpus of theory that has accumulated in regard to an issue, concept, theory, phenomena. The theoretical literature review helps to establish what theories already exist, the relationships between them, to what degree the existing theories have been investigated, and to develop new hypotheses to be tested. Often this form is used to help establish a lack of appropriate theories or reveal that current theories are inadequate for explaining new or emerging research problems. The unit of analysis can focus on a theoretical concept or a whole theory or framework.

NOTE : Most often the literature review will incorporate some combination of types. For example, a review that examines literature supporting or refuting an argument, assumption, or philosophical problem related to the research problem will also need to include writing supported by sources that establish the history of these arguments in the literature.

Baumeister, Roy F. and Mark R. Leary. "Writing Narrative Literature Reviews." Review of General Psychology 1 (September 1997): 311-320; Mark R. Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998; Kennedy, Mary M. "Defining a Literature." Educational Researcher 36 (April 2007): 139-147; Petticrew, Mark and Helen Roberts. Systematic Reviews in the Social Sciences: A Practical Guide . Malden, MA: Blackwell Publishers, 2006; Torracro, Richard. "Writing Integrative Literature Reviews: Guidelines and Examples." Human Resource Development Review 4 (September 2005): 356-367; Rocco, Tonette S. and Maria S. Plakhotnik. "Literature Reviews, Conceptual Frameworks, and Theoretical Frameworks: Terms, Functions, and Distinctions." Human Ressource Development Review 8 (March 2008): 120-130; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016.

Structure and Writing Style

I. Thinking About Your Literature Review

The structure of a literature review should include the following in support of understanding the research problem :

An overview of the subject, issue, or theory under consideration, along with the objectives of the literature review,
Division of works under review into themes or categories [e.g. works that support a particular position, those against, and those offering alternative approaches entirely],
An explanation of how each work is similar to and how it varies from the others,
Conclusions as to which pieces are best considered in their argument, are most convincing of their opinions, and make the greatest contribution to the understanding and development of their area of research.

The critical evaluation of each work should consider :

Provenance -- what are the author's credentials? Are the author's arguments supported by evidence [e.g. primary historical material, case studies, narratives, statistics, recent scientific findings]?
Methodology -- were the techniques used to identify, gather, and analyze the data appropriate to addressing the research problem? Was the sample size appropriate? Were the results effectively interpreted and reported?
Objectivity -- is the author's perspective even-handed or prejudicial? Is contrary data considered or is certain pertinent information ignored to prove the author's point?
Persuasiveness -- which of the author's theses are most convincing or least convincing?
Validity -- are the author's arguments and conclusions convincing? Does the work ultimately contribute in any significant way to an understanding of the subject?

II. Development of the Literature Review

Four Basic Stages of Writing 1. Problem formulation -- which topic or field is being examined and what are its component issues? 2. Literature search -- finding materials relevant to the subject being explored. 3. Data evaluation -- determining which literature makes a significant contribution to the understanding of the topic. 4. Analysis and interpretation -- discussing the findings and conclusions of pertinent literature.

Consider the following issues before writing the literature review: Clarify If your assignment is not specific about what form your literature review should take, seek clarification from your professor by asking these questions: 1. Roughly how many sources would be appropriate to include? 2. What types of sources should I review (books, journal articles, websites; scholarly versus popular sources)? 3. Should I summarize, synthesize, or critique sources by discussing a common theme or issue? 4. Should I evaluate the sources in any way beyond evaluating how they relate to understanding the research problem? 5. Should I provide subheadings and other background information, such as definitions and/or a history? Find Models Use the exercise of reviewing the literature to examine how authors in your discipline or area of interest have composed their literature review sections. Read them to get a sense of the types of themes you might want to look for in your own research or to identify ways to organize your final review. The bibliography or reference section of sources you've already read, such as required readings in the course syllabus, are also excellent entry points into your own research. Narrow the Topic The narrower your topic, the easier it will be to limit the number of sources you need to read in order to obtain a good survey of relevant resources. Your professor will probably not expect you to read everything that's available about the topic, but you'll make the act of reviewing easier if you first limit scope of the research problem. A good strategy is to begin by searching the USC Libraries Catalog for recent books about the topic and review the table of contents for chapters that focuses on specific issues. You can also review the indexes of books to find references to specific issues that can serve as the focus of your research. For example, a book surveying the history of the Israeli-Palestinian conflict may include a chapter on the role Egypt has played in mediating the conflict, or look in the index for the pages where Egypt is mentioned in the text. Consider Whether Your Sources are Current Some disciplines require that you use information that is as current as possible. This is particularly true in disciplines in medicine and the sciences where research conducted becomes obsolete very quickly as new discoveries are made. However, when writing a review in the social sciences, a survey of the history of the literature may be required. In other words, a complete understanding the research problem requires you to deliberately examine how knowledge and perspectives have changed over time. Sort through other current bibliographies or literature reviews in the field to get a sense of what your discipline expects. You can also use this method to explore what is considered by scholars to be a "hot topic" and what is not.

III. Ways to Organize Your Literature Review

Chronology of Events If your review follows the chronological method, you could write about the materials according to when they were published. This approach should only be followed if a clear path of research building on previous research can be identified and that these trends follow a clear chronological order of development. For example, a literature review that focuses on continuing research about the emergence of German economic power after the fall of the Soviet Union. By Publication Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on environmental studies of brown fields if the progression revealed, for example, a change in the soil collection practices of the researchers who wrote and/or conducted the studies. Thematic [“conceptual categories”] A thematic literature review is the most common approach to summarizing prior research in the social and behavioral sciences. Thematic reviews are organized around a topic or issue, rather than the progression of time, although the progression of time may still be incorporated into a thematic review. For example, a review of the Internet’s impact on American presidential politics could focus on the development of online political satire. While the study focuses on one topic, the Internet’s impact on American presidential politics, it would still be organized chronologically reflecting technological developments in media. The difference in this example between a "chronological" and a "thematic" approach is what is emphasized the most: themes related to the role of the Internet in presidential politics. Note that more authentic thematic reviews tend to break away from chronological order. A review organized in this manner would shift between time periods within each section according to the point being made. Methodological A methodological approach focuses on the methods utilized by the researcher. For the Internet in American presidential politics project, one methodological approach would be to look at cultural differences between the portrayal of American presidents on American, British, and French websites. Or the review might focus on the fundraising impact of the Internet on a particular political party. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed.

Other Sections of Your Literature Review Once you've decided on the organizational method for your literature review, the sections you need to include in the paper should be easy to figure out because they arise from your organizational strategy. In other words, a chronological review would have subsections for each vital time period; a thematic review would have subtopics based upon factors that relate to the theme or issue. However, sometimes you may need to add additional sections that are necessary for your study, but do not fit in the organizational strategy of the body. What other sections you include in the body is up to you. However, only include what is necessary for the reader to locate your study within the larger scholarship about the research problem.

Here are examples of other sections, usually in the form of a single paragraph, you may need to include depending on the type of review you write:

Current Situation : Information necessary to understand the current topic or focus of the literature review.
Sources Used : Describes the methods and resources [e.g., databases] you used to identify the literature you reviewed.
History : The chronological progression of the field, the research literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
Selection Methods : Criteria you used to select (and perhaps exclude) sources in your literature review. For instance, you might explain that your review includes only peer-reviewed [i.e., scholarly] sources.
Standards : Description of the way in which you present your information.
Questions for Further Research : What questions about the field has the review sparked? How will you further your research as a result of the review?

IV. Writing Your Literature Review

Once you've settled on how to organize your literature review, you're ready to write each section. When writing your review, keep in mind these issues.

Use Evidence A literature review section is, in this sense, just like any other academic research paper. Your interpretation of the available sources must be backed up with evidence [citations] that demonstrates that what you are saying is valid. Be Selective Select only the most important points in each source to highlight in the review. The type of information you choose to mention should relate directly to the research problem, whether it is thematic, methodological, or chronological. Related items that provide additional information, but that are not key to understanding the research problem, can be included in a list of further readings . Use Quotes Sparingly Some short quotes are appropriate if you want to emphasize a point, or if what an author stated cannot be easily paraphrased. Sometimes you may need to quote certain terminology that was coined by the author, is not common knowledge, or taken directly from the study. Do not use extensive quotes as a substitute for using your own words in reviewing the literature. Summarize and Synthesize Remember to summarize and synthesize your sources within each thematic paragraph as well as throughout the review. Recapitulate important features of a research study, but then synthesize it by rephrasing the study's significance and relating it to your own work and the work of others. Keep Your Own Voice While the literature review presents others' ideas, your voice [the writer's] should remain front and center. For example, weave references to other sources into what you are writing but maintain your own voice by starting and ending the paragraph with your own ideas and wording. Use Caution When Paraphrasing When paraphrasing a source that is not your own, be sure to represent the author's information or opinions accurately and in your own words. Even when paraphrasing an author’s work, you still must provide a citation to that work.

V. Common Mistakes to Avoid

These are the most common mistakes made in reviewing social science research literature.

Sources in your literature review do not clearly relate to the research problem;
You do not take sufficient time to define and identify the most relevant sources to use in the literature review related to the research problem;
Relies exclusively on secondary analytical sources rather than including relevant primary research studies or data;
Uncritically accepts another researcher's findings and interpretations as valid, rather than examining critically all aspects of the research design and analysis;
Does not describe the search procedures that were used in identifying the literature to review;
Reports isolated statistical results rather than synthesizing them in chi-squared or meta-analytic methods; and,
Only includes research that validates assumptions and does not consider contrary findings and alternative interpretations found in the literature.

Cook, Kathleen E. and Elise Murowchick. “Do Literature Review Skills Transfer from One Course to Another?” Psychology Learning and Teaching 13 (March 2014): 3-11; Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998; Jesson, Jill. Doing Your Literature Review: Traditional and Systematic Techniques . London: SAGE, 2011; Literature Review Handout. Online Writing Center. Liberty University; Literature Reviews. The Writing Center. University of North Carolina; Onwuegbuzie, Anthony J. and Rebecca Frels. Seven Steps to a Comprehensive Literature Review: A Multimodal and Cultural Approach . Los Angeles, CA: SAGE, 2016; Ridley, Diana. The Literature Review: A Step-by-Step Guide for Students . 2nd ed. Los Angeles, CA: SAGE, 2012; Randolph, Justus J. “A Guide to Writing the Dissertation Literature Review." Practical Assessment, Research, and Evaluation. vol. 14, June 2009; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016; Taylor, Dena. The Literature Review: A Few Tips On Conducting It. University College Writing Centre. University of Toronto; Writing a Literature Review. Academic Skills Centre. University of Canberra.

Writing Tip

Break Out of Your Disciplinary Box!

Thinking interdisciplinarily about a research problem can be a rewarding exercise in applying new ideas, theories, or concepts to an old problem. For example, what might cultural anthropologists say about the continuing conflict in the Middle East? In what ways might geographers view the need for better distribution of social service agencies in large cities than how social workers might study the issue? You don’t want to substitute a thorough review of core research literature in your discipline for studies conducted in other fields of study. However, particularly in the social sciences, thinking about research problems from multiple vectors is a key strategy for finding new solutions to a problem or gaining a new perspective. Consult with a librarian about identifying research databases in other disciplines; almost every field of study has at least one comprehensive database devoted to indexing its research literature.

Frodeman, Robert. The Oxford Handbook of Interdisciplinarity . New York: Oxford University Press, 2010.

Another Writing Tip

Don't Just Review for Content!

While conducting a review of the literature, maximize the time you devote to writing this part of your paper by thinking broadly about what you should be looking for and evaluating. Review not just what scholars are saying, but how are they saying it. Some questions to ask:

How are they organizing their ideas?
What methods have they used to study the problem?
What theories have been used to explain, predict, or understand their research problem?
What sources have they cited to support their conclusions?
How have they used non-textual elements [e.g., charts, graphs, figures, etc.] to illustrate key points?

When you begin to write your literature review section, you'll be glad you dug deeper into how the research was designed and constructed because it establishes a means for developing more substantial analysis and interpretation of the research problem.

Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1 998.

Yet Another Writing Tip

When Do I Know I Can Stop Looking and Move On?

Here are several strategies you can utilize to assess whether you've thoroughly reviewed the literature:

Look for repeating patterns in the research findings . If the same thing is being said, just by different people, then this likely demonstrates that the research problem has hit a conceptual dead end. At this point consider: Does your study extend current research? Does it forge a new path? Or, does is merely add more of the same thing being said?
Look at sources the authors cite to in their work . If you begin to see the same researchers cited again and again, then this is often an indication that no new ideas have been generated to address the research problem.
Search Google Scholar to identify who has subsequently cited leading scholars already identified in your literature review [see next sub-tab]. This is called citation tracking and there are a number of sources that can help you identify who has cited whom, particularly scholars from outside of your discipline. Here again, if the same authors are being cited again and again, this may indicate no new literature has been written on the topic.

Onwuegbuzie, Anthony J. and Rebecca Frels. Seven Steps to a Comprehensive Literature Review: A Multimodal and Cultural Approach . Los Angeles, CA: Sage, 2016; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016.

<< Previous: Theoretical Framework
Next: Citation Tracking >>
Last Updated: Apr 11, 2024 1:27 PM
URL: https://libguides.usc.edu/writingguide

The Writing Center • University of North Carolina at Chapel Hill

Literature Reviews

What this handout is about.

This handout will explain what literature reviews are and offer insights into the form and construction of literature reviews in the humanities, social sciences, and sciences.

Introduction

OK. You’ve got to write a literature review. You dust off a novel and a book of poetry, settle down in your chair, and get ready to issue a “thumbs up” or “thumbs down” as you leaf through the pages. “Literature review” done. Right?

Wrong! The “literature” of a literature review refers to any collection of materials on a topic, not necessarily the great literary texts of the world. “Literature” could be anything from a set of government pamphlets on British colonial methods in Africa to scholarly articles on the treatment of a torn ACL. And a review does not necessarily mean that your reader wants you to give your personal opinion on whether or not you liked these sources.

What is a literature review, then?

A literature review discusses published information in a particular subject area, and sometimes information in a particular subject area within a certain time period.

A literature review can be just a simple summary of the sources, but it usually has an organizational pattern and combines both summary and synthesis. A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information. It might give a new interpretation of old material or combine new with old interpretations. Or it might trace the intellectual progression of the field, including major debates. And depending on the situation, the literature review may evaluate the sources and advise the reader on the most pertinent or relevant.

But how is a literature review different from an academic research paper?

The main focus of an academic research paper is to develop a new argument, and a research paper is likely to contain a literature review as one of its parts. In a research paper, you use the literature as a foundation and as support for a new insight that you contribute. The focus of a literature review, however, is to summarize and synthesize the arguments and ideas of others without adding new contributions.

Why do we write literature reviews?

Literature reviews provide you with a handy guide to a particular topic. If you have limited time to conduct research, literature reviews can give you an overview or act as a stepping stone. For professionals, they are useful reports that keep them up to date with what is current in the field. For scholars, the depth and breadth of the literature review emphasizes the credibility of the writer in his or her field. Literature reviews also provide a solid background for a research paper’s investigation. Comprehensive knowledge of the literature of the field is essential to most research papers.

Who writes these things, anyway?

Literature reviews are written occasionally in the humanities, but mostly in the sciences and social sciences; in experiment and lab reports, they constitute a section of the paper. Sometimes a literature review is written as a paper in itself.

Let’s get to it! What should I do before writing the literature review?

If your assignment is not very specific, seek clarification from your instructor:

Roughly how many sources should you include?
What types of sources (books, journal articles, websites)?
Should you summarize, synthesize, or critique your sources by discussing a common theme or issue?
Should you evaluate your sources?
Should you provide subheadings and other background information, such as definitions and/or a history?

Find models

Look for other literature reviews in your area of interest or in the discipline and read them to get a sense of the types of themes you might want to look for in your own research or ways to organize your final review. You can simply put the word “review” in your search engine along with your other topic terms to find articles of this type on the Internet or in an electronic database. The bibliography or reference section of sources you’ve already read are also excellent entry points into your own research.

Narrow your topic

There are hundreds or even thousands of articles and books on most areas of study. The narrower your topic, the easier it will be to limit the number of sources you need to read in order to get a good survey of the material. Your instructor will probably not expect you to read everything that’s out there on the topic, but you’ll make your job easier if you first limit your scope.

Keep in mind that UNC Libraries have research guides and to databases relevant to many fields of study. You can reach out to the subject librarian for a consultation: https://library.unc.edu/support/consultations/ .

And don’t forget to tap into your professor’s (or other professors’) knowledge in the field. Ask your professor questions such as: “If you had to read only one book from the 90’s on topic X, what would it be?” Questions such as this help you to find and determine quickly the most seminal pieces in the field.

Consider whether your sources are current

Some disciplines require that you use information that is as current as possible. In the sciences, for instance, treatments for medical problems are constantly changing according to the latest studies. Information even two years old could be obsolete. However, if you are writing a review in the humanities, history, or social sciences, a survey of the history of the literature may be what is needed, because what is important is how perspectives have changed through the years or within a certain time period. Try sorting through some other current bibliographies or literature reviews in the field to get a sense of what your discipline expects. You can also use this method to consider what is currently of interest to scholars in this field and what is not.

Strategies for writing the literature review

Find a focus.

A literature review, like a term paper, is usually organized around ideas, not the sources themselves as an annotated bibliography would be organized. This means that you will not just simply list your sources and go into detail about each one of them, one at a time. No. As you read widely but selectively in your topic area, consider instead what themes or issues connect your sources together. Do they present one or different solutions? Is there an aspect of the field that is missing? How well do they present the material and do they portray it according to an appropriate theory? Do they reveal a trend in the field? A raging debate? Pick one of these themes to focus the organization of your review.

Convey it to your reader

A literature review may not have a traditional thesis statement (one that makes an argument), but you do need to tell readers what to expect. Try writing a simple statement that lets the reader know what is your main organizing principle. Here are a couple of examples:

The current trend in treatment for congestive heart failure combines surgery and medicine. More and more cultural studies scholars are accepting popular media as a subject worthy of academic consideration.

Consider organization

You’ve got a focus, and you’ve stated it clearly and directly. Now what is the most effective way of presenting the information? What are the most important topics, subtopics, etc., that your review needs to include? And in what order should you present them? Develop an organization for your review at both a global and local level:

First, cover the basic categories

Just like most academic papers, literature reviews also must contain at least three basic elements: an introduction or background information section; the body of the review containing the discussion of sources; and, finally, a conclusion and/or recommendations section to end the paper. The following provides a brief description of the content of each:

Introduction: Gives a quick idea of the topic of the literature review, such as the central theme or organizational pattern.
Body: Contains your discussion of sources and is organized either chronologically, thematically, or methodologically (see below for more information on each).
Conclusions/Recommendations: Discuss what you have drawn from reviewing literature so far. Where might the discussion proceed?

Organizing the body

Once you have the basic categories in place, then you must consider how you will present the sources themselves within the body of your paper. Create an organizational method to focus this section even further.

To help you come up with an overall organizational framework for your review, consider the following scenario:

You’ve decided to focus your literature review on materials dealing with sperm whales. This is because you’ve just finished reading Moby Dick, and you wonder if that whale’s portrayal is really real. You start with some articles about the physiology of sperm whales in biology journals written in the 1980’s. But these articles refer to some British biological studies performed on whales in the early 18th century. So you check those out. Then you look up a book written in 1968 with information on how sperm whales have been portrayed in other forms of art, such as in Alaskan poetry, in French painting, or on whale bone, as the whale hunters in the late 19th century used to do. This makes you wonder about American whaling methods during the time portrayed in Moby Dick, so you find some academic articles published in the last five years on how accurately Herman Melville portrayed the whaling scene in his novel.

Now consider some typical ways of organizing the sources into a review:

Chronological: If your review follows the chronological method, you could write about the materials above according to when they were published. For instance, first you would talk about the British biological studies of the 18th century, then about Moby Dick, published in 1851, then the book on sperm whales in other art (1968), and finally the biology articles (1980s) and the recent articles on American whaling of the 19th century. But there is relatively no continuity among subjects here. And notice that even though the sources on sperm whales in other art and on American whaling are written recently, they are about other subjects/objects that were created much earlier. Thus, the review loses its chronological focus.
By publication: Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on biological studies of sperm whales if the progression revealed a change in dissection practices of the researchers who wrote and/or conducted the studies.
By trend: A better way to organize the above sources chronologically is to examine the sources under another trend, such as the history of whaling. Then your review would have subsections according to eras within this period. For instance, the review might examine whaling from pre-1600-1699, 1700-1799, and 1800-1899. Under this method, you would combine the recent studies on American whaling in the 19th century with Moby Dick itself in the 1800-1899 category, even though the authors wrote a century apart.
Thematic: Thematic reviews of literature are organized around a topic or issue, rather than the progression of time. However, progression of time may still be an important factor in a thematic review. For instance, the sperm whale review could focus on the development of the harpoon for whale hunting. While the study focuses on one topic, harpoon technology, it will still be organized chronologically. The only difference here between a “chronological” and a “thematic” approach is what is emphasized the most: the development of the harpoon or the harpoon technology.But more authentic thematic reviews tend to break away from chronological order. For instance, a thematic review of material on sperm whales might examine how they are portrayed as “evil” in cultural documents. The subsections might include how they are personified, how their proportions are exaggerated, and their behaviors misunderstood. A review organized in this manner would shift between time periods within each section according to the point made.
Methodological: A methodological approach differs from the two above in that the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the “methods” of the researcher or writer. For the sperm whale project, one methodological approach would be to look at cultural differences between the portrayal of whales in American, British, and French art work. Or the review might focus on the economic impact of whaling on a community. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed. Once you’ve decided on the organizational method for the body of the review, the sections you need to include in the paper should be easy to figure out. They should arise out of your organizational strategy. In other words, a chronological review would have subsections for each vital time period. A thematic review would have subtopics based upon factors that relate to the theme or issue.

Sometimes, though, you might need to add additional sections that are necessary for your study, but do not fit in the organizational strategy of the body. What other sections you include in the body is up to you. Put in only what is necessary. Here are a few other sections you might want to consider:

Current Situation: Information necessary to understand the topic or focus of the literature review.
History: The chronological progression of the field, the literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
Methods and/or Standards: The criteria you used to select the sources in your literature review or the way in which you present your information. For instance, you might explain that your review includes only peer-reviewed articles and journals.

Questions for Further Research: What questions about the field has the review sparked? How will you further your research as a result of the review?

Begin composing

Once you’ve settled on a general pattern of organization, you’re ready to write each section. There are a few guidelines you should follow during the writing stage as well. Here is a sample paragraph from a literature review about sexism and language to illuminate the following discussion:

However, other studies have shown that even gender-neutral antecedents are more likely to produce masculine images than feminine ones (Gastil, 1990). Hamilton (1988) asked students to complete sentences that required them to fill in pronouns that agreed with gender-neutral antecedents such as “writer,” “pedestrian,” and “persons.” The students were asked to describe any image they had when writing the sentence. Hamilton found that people imagined 3.3 men to each woman in the masculine “generic” condition and 1.5 men per woman in the unbiased condition. Thus, while ambient sexism accounted for some of the masculine bias, sexist language amplified the effect. (Source: Erika Falk and Jordan Mills, “Why Sexist Language Affects Persuasion: The Role of Homophily, Intended Audience, and Offense,” Women and Language19:2).

Use evidence

In the example above, the writers refer to several other sources when making their point. A literature review in this sense is just like any other academic research paper. Your interpretation of the available sources must be backed up with evidence to show that what you are saying is valid.

Be selective

Select only the most important points in each source to highlight in the review. The type of information you choose to mention should relate directly to the review’s focus, whether it is thematic, methodological, or chronological.

Use quotes sparingly

Falk and Mills do not use any direct quotes. That is because the survey nature of the literature review does not allow for in-depth discussion or detailed quotes from the text. Some short quotes here and there are okay, though, if you want to emphasize a point, or if what the author said just cannot be rewritten in your own words. Notice that Falk and Mills do quote certain terms that were coined by the author, not common knowledge, or taken directly from the study. But if you find yourself wanting to put in more quotes, check with your instructor.

Summarize and synthesize

Remember to summarize and synthesize your sources within each paragraph as well as throughout the review. The authors here recapitulate important features of Hamilton’s study, but then synthesize it by rephrasing the study’s significance and relating it to their own work.

Keep your own voice

While the literature review presents others’ ideas, your voice (the writer’s) should remain front and center. Notice that Falk and Mills weave references to other sources into their own text, but they still maintain their own voice by starting and ending the paragraph with their own ideas and their own words. The sources support what Falk and Mills are saying.

Use caution when paraphrasing

When paraphrasing a source that is not your own, be sure to represent the author’s information or opinions accurately and in your own words. In the preceding example, Falk and Mills either directly refer in the text to the author of their source, such as Hamilton, or they provide ample notation in the text when the ideas they are mentioning are not their own, for example, Gastil’s. For more information, please see our handout on plagiarism .

Revise, revise, revise

Draft in hand? Now you’re ready to revise. Spending a lot of time revising is a wise idea, because your main objective is to present the material, not the argument. So check over your review again to make sure it follows the assignment and/or your outline. Then, just as you would for most other academic forms of writing, rewrite or rework the language of your review so that you’ve presented your information in the most concise manner possible. Be sure to use terminology familiar to your audience; get rid of unnecessary jargon or slang. Finally, double check that you’ve documented your sources and formatted the review appropriately for your discipline. For tips on the revising and editing process, see our handout on revising drafts .

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

Anson, Chris M., and Robert A. Schwegler. 2010. The Longman Handbook for Writers and Readers , 6th ed. New York: Longman.

Jones, Robert, Patrick Bizzaro, and Cynthia Selfe. 1997. The Harcourt Brace Guide to Writing in the Disciplines . New York: Harcourt Brace.

Lamb, Sandra E. 1998. How to Write It: A Complete Guide to Everything You’ll Ever Write . Berkeley: Ten Speed Press.

Rosen, Leonard J., and Laurence Behrens. 2003. The Allyn & Bacon Handbook , 5th ed. New York: Longman.

Troyka, Lynn Quittman, and Doug Hesse. 2016. Simon and Schuster Handbook for Writers , 11th ed. London: Pearson.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

Make a Gift

UWF Libraries

Literature Review: Conducting & Writing

Sample Literature Reviews
Steps for Conducting a Lit Review
Finding "The Literature"
Organizing/Writing
APA Style This link opens in a new window
Chicago: Notes Bibliography This link opens in a new window
MLA Style This link opens in a new window

Sample Lit Reviews from Communication Arts

Have an exemplary literature review.

Literature Review Sample 1
Literature Review Sample 2
Literature Review Sample 3

Have you written a stellar literature review you care to share for teaching purposes?

Are you an instructor who has received an exemplary literature review and have permission from the student to post?

Please contact Britt McGowan at [email protected] for inclusion in this guide. All disciplines welcome and encouraged.

<< Previous: MLA Style
Next: Get Help! >>
Last Updated: Mar 22, 2024 9:37 AM
URL: https://libguides.uwf.edu/litreview

Research Methods

Getting Started
Literature Review Research
Research Design
Research Design By Discipline
SAGE Research Methods
Teaching with SAGE Research Methods

Literature Review

What is a Literature Review?
What is NOT a Literature Review?
Purposes of a Literature Review
Types of Literature Reviews
Literature Reviews vs. Systematic Reviews
Systematic vs. Meta-Analysis

Literature Review is a comprehensive survey of the works published in a particular field of study or line of research, usually over a specific period of time, in the form of an in-depth, critical bibliographic essay or annotated list in which attention is drawn to the most significant works.

Also, we can define a literature review as the collected body of scholarly works related to a topic:

Summarizes and analyzes previous research relevant to a topic
Includes scholarly books and articles published in academic journals
Can be an specific scholarly paper or a section in a research paper

The objective of a Literature Review is to find previous published scholarly works relevant to an specific topic

Help gather ideas or information
Keep up to date in current trends and findings
Help develop new questions

A literature review is important because it:

Explains the background of research on a topic.
Demonstrates why a topic is significant to a subject area.
Helps focus your own research questions or problems
Discovers relationships between research studies/ideas.
Suggests unexplored ideas or populations
Identifies major themes, concepts, and researchers on a topic.
Tests assumptions; may help counter preconceived ideas and remove unconscious bias.
Identifies critical gaps, points of disagreement, or potentially flawed methodology or theoretical approaches.
Indicates potential directions for future research.

All content in this section is from Literature Review Research from Old Dominion University

Keep in mind the following, a literature review is NOT:

Not an essay

Not an annotated bibliography in which you summarize each article that you have reviewed. A literature review goes beyond basic summarizing to focus on the critical analysis of the reviewed works and their relationship to your research question.

Not a research paper where you select resources to support one side of an issue versus another. A lit review should explain and consider all sides of an argument in order to avoid bias, and areas of agreement and disagreement should be highlighted.

A literature review serves several purposes. For example, it

provides thorough knowledge of previous studies; introduces seminal works.
helps focus one’s own research topic.
identifies a conceptual framework for one’s own research questions or problems; indicates potential directions for future research.
suggests previously unused or underused methodologies, designs, quantitative and qualitative strategies.
identifies gaps in previous studies; identifies flawed methodologies and/or theoretical approaches; avoids replication of mistakes.
helps the researcher avoid repetition of earlier research.
suggests unexplored populations.
determines whether past studies agree or disagree; identifies controversy in the literature.
tests assumptions; may help counter preconceived ideas and remove unconscious bias.

As Kennedy (2007) notes*, it is important to think of knowledge in a given field as consisting of three layers. First, there are the primary studies that researchers conduct and publish. Second are the reviews of those studies that summarize and offer new interpretations built from and often extending beyond the original studies. Third, there are the perceptions, conclusions, opinion, and interpretations that are shared informally that become part of the lore of field. In composing a literature review, it is important to note that it is often this third layer of knowledge that is cited as "true" even though it often has only a loose relationship to the primary studies and secondary literature reviews.

Given this, while literature reviews are designed to provide an overview and synthesis of pertinent sources you have explored, there are several approaches to how they can be done, depending upon the type of analysis underpinning your study. Listed below are definitions of types of literature reviews:

Argumentative Review This form examines literature selectively in order to support or refute an argument, deeply imbedded assumption, or philosophical problem already established in the literature. The purpose is to develop a body of literature that establishes a contrarian viewpoint. Given the value-laden nature of some social science research [e.g., educational reform; immigration control], argumentative approaches to analyzing the literature can be a legitimate and important form of discourse. However, note that they can also introduce problems of bias when they are used to to make summary claims of the sort found in systematic reviews.

Integrative Review Considered a form of research that reviews, critiques, and synthesizes representative literature on a topic in an integrated way such that new frameworks and perspectives on the topic are generated. The body of literature includes all studies that address related or identical hypotheses. A well-done integrative review meets the same standards as primary research in regard to clarity, rigor, and replication.

Historical Review Few things rest in isolation from historical precedent. Historical reviews are focused on examining research throughout a period of time, often starting with the first time an issue, concept, theory, phenomena emerged in the literature, then tracing its evolution within the scholarship of a discipline. The purpose is to place research in a historical context to show familiarity with state-of-the-art developments and to identify the likely directions for future research.

Methodological Review A review does not always focus on what someone said [content], but how they said it [method of analysis]. This approach provides a framework of understanding at different levels (i.e. those of theory, substantive fields, research approaches and data collection and analysis techniques), enables researchers to draw on a wide variety of knowledge ranging from the conceptual level to practical documents for use in fieldwork in the areas of ontological and epistemological consideration, quantitative and qualitative integration, sampling, interviewing, data collection and data analysis, and helps highlight many ethical issues which we should be aware of and consider as we go through our study.

Theoretical Review The purpose of this form is to concretely examine the corpus of theory that has accumulated in regard to an issue, concept, theory, phenomena. The theoretical literature review help establish what theories already exist, the relationships between them, to what degree the existing theories have been investigated, and to develop new hypotheses to be tested. Often this form is used to help establish a lack of appropriate theories or reveal that current theories are inadequate for explaining new or emerging research problems. The unit of analysis can focus on a theoretical concept or a whole theory or framework.

* Kennedy, Mary M. "Defining a Literature." Educational Researcher 36 (April 2007): 139-147.

All content in this section is from The Literature Review created by Dr. Robert Larabee USC

Robinson, P. and Lowe, J. (2015), Literature reviews vs systematic reviews. Australian and New Zealand Journal of Public Health, 39: 103-103. doi: 10.1111/1753-6405.12393

What's in the name? The difference between a Systematic Review and a Literature Review, and why it matters . By Lynn Kysh from University of Southern California

Systematic review or meta-analysis?

A systematic review answers a defined research question by collecting and summarizing all empirical evidence that fits pre-specified eligibility criteria.

A meta-analysis is the use of statistical methods to summarize the results of these studies.

Systematic reviews, just like other research articles, can be of varying quality. They are a significant piece of work (the Centre for Reviews and Dissemination at York estimates that a team will take 9-24 months), and to be useful to other researchers and practitioners they should have:

clearly stated objectives with pre-defined eligibility criteria for studies
explicit, reproducible methodology
a systematic search that attempts to identify all studies
assessment of the validity of the findings of the included studies (e.g. risk of bias)
systematic presentation, and synthesis, of the characteristics and findings of the included studies

Not all systematic reviews contain meta-analysis.

Meta-analysis is the use of statistical methods to summarize the results of independent studies. By combining information from all relevant studies, meta-analysis can provide more precise estimates of the effects of health care than those derived from the individual studies included within a review. More information on meta-analyses can be found in Cochrane Handbook, Chapter 9 .

A meta-analysis goes beyond critique and integration and conducts secondary statistical analysis on the outcomes of similar studies. It is a systematic review that uses quantitative methods to synthesize and summarize the results.

An advantage of a meta-analysis is the ability to be completely objective in evaluating research findings. Not all topics, however, have sufficient research evidence to allow a meta-analysis to be conducted. In that case, an integrative review is an appropriate strategy.

Some of the content in this section is from Systematic reviews and meta-analyses: step by step guide created by Kate McAllister.

<< Previous: Getting Started
Next: Research Design >>
Last Updated: Aug 21, 2023 4:07 PM
URL: https://guides.lib.udel.edu/researchmethods

CPS Online Library Research Guide (UNH Manchester Library): Create a Literature Review

Home & Table of Contents
Different Types of Information
The Savvy Information Consumer
Primary & Secondary Sources
Periodical Literature
Peer Review
Research Glossary
Business Research Databases
Understanding the Assignment
Preliminary Considerations
7 Steps to Completing a Research Assignment
Define the Topic
Find & Evaluate Your Sources
Research Integrity & Citing Your Sources
Searching for Information
Evaluating Information
How to Read an Academic Journal Article This link opens in a new window
Evaluating Social Media Sources
Writing Your Research Paper
Create a Literature Review
Summarize an Article
How to Write an Abstract
How to Write a Book Review
How to Do an Annotated Bibliography
Finding Professional Organizations
Find Key Journals in Your Field of Study
Find Peer-Reviewed Articles
Write a Research Paper Proposal
Research a Company This link opens in a new window
Citing Your Sources
Avoiding Plagiarism
NHCUC Libraries
Other Types of Research
Academic Libraries in NH
Government Documents
Using Google for Academic Research
Information Literacy
Developing Effective Library Research Assignments
Using Permalinks
Primary Source Websites

What is a literature review?

A literature review discusses published information in a particular subject area, and sometimes information in a particular subject area within a certain time period.

But how is a literature review different from an academic research paper?

Why do we write literature reviews?

Strategies for writing the literature review

Find a focus.

Convey it to your reader

The current trend in treatment for congestive heart failure combines surgery and medicine.

More and more cultural studies scholars are accepting popular media as a subject worthy of academic consideration.

Consider organization

You’ve got a focus, and you’ve stated it clearly and directly. Now what is the most effective way of presenting the information? What are the most important topics, subtopics, etc ., that your review needs to include? And in what order should you present them? Develop an organization for your review at both a global and local level:

First, cover the basic categories

Just like most academic papers, literature reviews are likely to contain at least three basic elements: an introduction or background information section; the body of the review containing the discussion of sources; and, finally, a conclusion and/or recommendations section to end the paper. The following provides a brief description of the content of each:

Introduction: Gives a quick idea of the topic of the literature review, such as the central theme or organizational pattern.
Body: Contains your discussion of sources and is organized either chronologically, thematically, or methodologically (see below for more information on each).
Conclusions/Recommendations: Discuss what you have drawn from reviewing literature so far. Where might the discussion proceed?

Organizing the body

To help you come up with an overall organizational framework for your review, consider the following scenario:

Now consider some typical ways of organizing the sources into a review:

Chronological: If your review follows the chronological method, you could write about the materials above according to when they were published. For instance, first you would talk about the British biological studies of the 18th century, then about Moby Dick, published in 1851, then the book on sperm whales in other art (1968), and finally the biology articles (1980s) and the recent articles on American whaling of the 19th century. But there is relatively no continuity among subjects here. And notice that even though the sources on sperm whales in other art and on American whaling are written recently, they are about other subjects/objects that were created much earlier. Thus, the review loses its chronological focus.
By publication: Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on biological studies of sperm whales if the progression revealed a change in dissection practices of the researchers who wrote and/or conducted the studies.
By trend: A better way to organize the above sources chronologically is to examine the sources under another trend, such as the history of whaling. Then your review would have subsections according to eras within this period. For instance, the review might examine whaling from pre-1600-1699, 1700-1799, and 1800-1899. Under this method, you would combine the recent studies on American whaling in the 19th century with Moby Dick itself in the 1800-1899 category, even though the authors wrote a century apart.
Thematic: Thematic reviews of literature are organized around a topic or issue, rather than the progression of time. However, progression of time may still be an important factor in a thematic review. For instance, the sperm whale review could focus on the development of the harpoon for whale hunting. While the study focuses on one topic, harpoon technology, it will still be organized chronologically. The only difference here between a “chronological” and a “thematic” approach is what is emphasized the most: the development of the harpoon or the harpoon technology.But more authentic thematic reviews tend to break away from chronological order. For instance, a thematic review of material on sperm whales might examine how they are portrayed as “evil” in cultural documents. The subsections might include how they are personified, how their proportions are exaggerated, and their behaviors misunderstood. A review organized in this manner would shift between time periods within each section according to the point made.
Methodological: A methodological approach differs from the two above in that the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the “methods” of the researcher or writer. For the sperm whale project, one methodological approach would be to look at cultural differences between the portrayal of whales in American, British, and French art work. Or the review might focus on the economic impact of whaling on a community. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed. Once you’ve decided on the organizational method for the body of the review, the sections you need to include in the paper should be easy to figure out. They should arise out of your organizational strategy. In other words, a chronological review would have subsections for each vital time period. A thematic review would have subtopics based upon factors that relate to the theme or issue.

Current Situation: Information necessary to understand the topic or focus of the literature review.
History: The chronological progression of the field, the literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
Methods and/or Standards: The criteria you used to select the sources in your literature review or the way in which you present your information. For instance, you might explain that your review includes only peer-reviewed articles and journals.

Questions for Further Research: What questions about the field has the review sparked? How will you further your research as a result of the review?

Attribution

"Create a Literature Review" is derivative of Literature Reviews by The Writing Center, University of North Carolina at Chapel Hill licensed Creative Commons Attribution-NonCommercial-NoDerivs 4.0 License .

<< Previous: Other Types of Research Assignments
Next: Summarize an Article >>
Last Updated: Apr 9, 2024 2:30 PM
URL: https://libraryguides.unh.edu/CPSonlineLibraryResearch

Toward a framework for selecting indicators of measuring sustainability and circular economy in the agri-food sector: a systematic literature review

LIFE CYCLE SUSTAINABILITY ASSESSMENT
Published: 02 March 2022

Cite this article

Cecilia Silvestri ORCID: orcid.org/0000-0003-2528-601X 1 ,
Luca Silvestri ORCID: orcid.org/0000-0002-6754-899X 2 ,
Michela Piccarozzi ORCID: orcid.org/0000-0001-9717-9462 1 &
Alessandro Ruggieri 1

2865 Accesses

11 Citations

9 Altmetric

Explore all metrics

A Correction to this article was published on 24 March 2022

This article has been updated

The implementation of sustainability and circular economy (CE) models in agri-food production can promote resource efficiency, reduce environmental burdens, and ensure improved and socially responsible systems. In this context, indicators for the measurement of sustainability play a crucial role. Indicators can measure CE strategies aimed to preserve functions, products, components, materials, or embodied energy. Although there is broad literature describing sustainability and CE indicators, no study offers such a comprehensive framework of indicators for measuring sustainability and CE in the agri-food sector.

Starting from this central research gap, a systematic literature review has been developed to measure the sustainability in the agri-food sector and, based on these findings, to understand how indicators are used and for which specific purposes.

The analysis of the results allowed us to classify the sample of articles in three main clusters (“Assessment-LCA,” “Best practice,” and “Decision-making”) and has shown increasing attention to the three pillars of sustainability (triple bottom line). In this context, an integrated approach of indicators (environmental, social, and economic) offers the best solution to ensure an easier transition to sustainability.

Conclusions

The sample analysis facilitated the identification of new categories of impact that deserve attention, such as the cooperation among stakeholders in the supply chain and eco-innovation.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price includes VAT (Russian Federation)

Instant access to the full article PDF.

Rent this article via DeepDyve

Institutional subscriptions

Source: Authors’ elaboration. Notes: The graph shows the temporal distribution of the articles under analysis

Source: Authors’ elaborations. Notes: The graph shows the time distribution of articles from the three major journals

Source: Authors’ elaboration. Notes: The graph shows the composition of the sample according to the three clusters identified by the analysis

Source: Authors’ elaboration. Notes: The graph shows the distribution of articles over time by cluster

Source: Authors’ elaboration. Notes: The graph shows the network visualization

Source: Authors’ elaboration. Notes: The graph shows the overlay visualization

Source: Authors’ elaboration. Notes: The graph shows the classification of articles by scientific field

Source: Authors’ elaboration. Notes: Article classification based on their cluster to which they belong and scientific field

Source: Authors’ elaboration

Source: Authors’ elaboration. Notes: The graph shows the distribution of items over time based on TBL

Source: Authors’ elaboration. Notes: The graph shows the Pareto diagram highlighting the most used indicators in literature for measuring sustainability in the agri-food sector

Source: Authors’ elaboration. Notes: The graph shows the distribution over time of articles divided into conceptual and empirical

Source: Authors’ elaboration. Notes: The graph shows the classification of articles, divided into conceptual and empirical, in-depth analysis

Source: Authors’ elaboration. Notes: The graph shows the geographical distribution of the authors

Source: Authors’ elaboration. Notes: The graph shows the distribution of authors according to the continent from which they originate

Source: Authors’ elaboration. Notes: The graph shows the time distribution of publication of authors according to the continent from which they originate

Source: Authors’ elaboration. Notes: Sustainability measurement indicators and impact categories of LCA, S-LCA, and LCC tools should be integrated in order to provide stakeholders with best practices as guidelines and tools to support both decision-making and measurement, according to the circular economy approach

The socio-economic performance of agroecology. A review

Ioanna Mouratiadou, Alexander Wezel, … Paolo Bàrberi

The Circular Economy: An Interdisciplinary Exploration of the Concept and Application in a Global Context

Alan Murray, Keith Skene & Kathryn Haynes

The sustainability of “local” food: a review for policy-makers

Alexander J. Stein & Fabien Santini

Change history

24 march 2022.

A Correction to this paper has been published: https://doi.org/10.1007/s11367-022-02038-9

Acero AP, Rodriguez C, Ciroth A (2017) LCIA methods: impact assessment methods in life cycle assessment and their impact categories. Version 1.5.6. Green Delta 1–23

Accorsi R, Versari L, Manzini R (2015) Glass vs. plastic: Life cycle assessment of extra-virgin olive oil bottles across global supply chains. Sustain 7:2818–2840. https://doi.org/10.3390/su7032818

Adjei-Bamfo P, Maloreh-Nyamekye T, Ahenkan A (2019) The role of e-government in sustainable public procurement in developing countries: a systematic literature review. Resour Conserv Recycl 142:189–203. https://doi.org/10.1016/j.resconrec.2018.12.001

Article Google Scholar

Aivazidou E, Tsolakis N, Vlachos D, Iakovou E (2015) Water footprint management policies for agrifood supply chains: a critical taxonomy and a system dynamics modelling approach. Chem Eng Trans 43:115–120. https://doi.org/10.3303/CET1543020

Alhaddi H (2015) Triple bottom line and sustainability: a literature review. Bus Manag Stud 1:6–10

Allaoui H, Guo Y, Sarkis J (2019) Decision support for collaboration planning in sustainable supply chains. J Clean Prod 229:761–774. https://doi.org/10.1016/j.jclepro.2019.04.367

Alshqaqeeq F, Amin Esmaeili M, Overcash M, Twomey J (2020) Quantifying hospital services by carbon footprint: a systematic literature review of patient care alternatives. Resour Conserv Recycl 154:104560. https://doi.org/10.1016/j.resconrec.2019.104560

Anwar F, Chaudhry FN, Nazeer S et al (2016) Causes of ozone layer depletion and its effects on human: review. Atmos Clim Sci 06:129–134. https://doi.org/10.4236/acs.2016.61011

Aquilani B, Silvestri C, Ruggieri A (2016). A Systematic Literature Review on Total Quality Management Critical Success Factors and the Identification of New Avenues of Research. https://doi.org/10.1108/TQM-01-2016-0003

Aramyan L, Hoste R, Van Den Broek W et al (2011) Towards sustainable food production: a scenario study of the European pork sector. J Chain Netw Sci 11:177–189. https://doi.org/10.3920/JCNS2011.Qpork8

Arfini F, Antonioli F, Cozzi E et al (2019) Sustainability, innovation and rural development: the case of Parmigiano-Reggiano PDO. Sustain 11:1–17. https://doi.org/10.3390/su11184978

Assembly UG (2005) Resolution adopted by the general assembly. New York, NY

Avilés-Palacios C, Rodríguez-Olalla A (2021) The sustainability of waste management models in circular economies. Sustain 13:1–19. https://doi.org/10.3390/su13137105

Azevedo SG, Silva ME, Matias JCO, Dias GP (2018) The influence of collaboration initiatives on the sustainability of the cashew supply chain. Sustain 10:1–29. https://doi.org/10.3390/su10062075

Bajaj S, Garg R, Sethi M (2016) Total quality management: a critical literature review using Pareto analysis. Int J Product Perform Manag 67:128–154

Banasik A, Kanellopoulos A, Bloemhof-Ruwaard JM, Claassen GDH (2019) Accounting for uncertainty in eco-efficient agri-food supply chains: a case study for mushroom production planning. J Clean Prod 216:249–256. https://doi.org/10.1016/j.jclepro.2019.01.153

Barth H, Ulvenblad PO, Ulvenblad P (2017) Towards a conceptual framework of sustainable business model innovation in the agri-food sector: a systematic literature review. Sustain 9. https://doi.org/10.3390/su9091620

Bastas A, Liyanage K (2018) Sustainable supply chain quality management: a systematic review

Beckerman W (1992) Economic growth and the environment: whose growth? Whose environment? World Dev 20:481–496. https://doi.org/10.1016/0305-750X(92)90038-W

Belaud JP, Prioux N, Vialle C, Sablayrolles C (2019) Big data for agri-food 4.0: application to sustainability management for by-products supply chain. Comput Ind 111:41–50. https://doi.org/10.1016/j.compind.2019.06.006

Bele B, Norderhaug A, Sickel H (2018) Localized agri-food systems and biodiversity. Agric 8. https://doi.org/10.3390/agriculture8020022

Bilali H El, Calabrese G, Iannetta M et al (2020) Environmental sustainability of typical agro-food products: a scientifically sound and user friendly approach. New Medit 19:69–83. https://doi.org/10.30682/nm2002e

Blanc S, Massaglia S, Brun F et al (2019) Use of bio-based plastics in the fruit supply chain: an integrated approach to assess environmental, economic, and social sustainability. Sustain 11. https://doi.org/10.3390/su11092475

Bloemhof JM, van der Vorst JGAJ, Bastl M, Allaoui H (2015) Sustainability assessment of food chain logistics. Int J Logist Res Appl 18:101–117. https://doi.org/10.1080/13675567.2015.1015508

Bonisoli L, Galdeano-Gómez E, Piedra-Muñoz L (2018) Deconstructing criteria and assessment tools to build agri-sustainability indicators and support farmers’ decision-making process. J Clean Prod 182:1080–1094. https://doi.org/10.1016/j.jclepro.2018.02.055

Bonisoli L, Galdeano-Gómez E, Piedra-Muñoz L, Pérez-Mesa JC (2019) Benchmarking agri-food sustainability certifications: evidences from applying SAFA in the Ecuadorian banana agri-system. J Clean Prod 236. https://doi.org/10.1016/j.jclepro.2019.07.054

Bornmann L, Haunschild R, Hug SE (2018) Visualizing the context of citations referencing papers published by Eugene Garfield: a new type of keyword co-occurrence analysis. Scientometrics 114:427–437. https://doi.org/10.1007/s11192-017-2591-8

Boulding KE (1966) The economics of the coming spaceship earth. New York, 1-17

Bracquené E, Dewulf W, Duflou JR (2020) Measuring the performance of more circular complex product supply chains. Resour Conserv Recycl 154:104608. https://doi.org/10.1016/j.resconrec.2019.104608

Burck J, Hagen U, Bals C et al (2021) Climate Change Performance Index

Calisto Friant M, Vermeulen WJV, Salomone R (2020) A typology of circular economy discourses: navigating the diverse visions of a contested paradigm. Resour Conserv Recycl 161:104917. https://doi.org/10.1016/j.resconrec.2020.104917

Campbell BM, Beare DJ, Bennett EM et al (2017) Agriculture production as a major driver of the earth system exceeding planetary boundaries. Ecol Soc 22. https://doi.org/10.5751/ES-09595-220408

Capitanio F, Coppola A, Pascucci S (2010) Product and process innovation in the Italian food industry. Agribusiness 26:503–518. https://doi.org/10.1002/agr.20239

Caputo P, Zagarella F, Cusenza MA et al (2020) Energy-environmental assessment of the UIA-OpenAgri case study as urban regeneration project through agriculture. Sci Total Environ 729:138819. https://doi.org/10.1016/j.scitotenv.2020.138819

Article CAS Google Scholar

Chabowski BR, Mena JA, Gonzalez-Padron TL (2011) The structure of sustainability research in marketing, 1958–2008: a basis for future research opportunities. J Acad Mark Sci 39:55–70. https://doi.org/10.1007/s11747-010-0212-7

Chadegani AA, Salehi H, Yunus M et al (2017) A comparison between two main academic literature collections : Web of Science and Scopus databases. Asian Soc Sci 9:18–26. https://doi.org/10.5539/ass.v9n5p18

Chams N, Guesmi B, Gil JM (2020) Beyond scientific contribution: assessment of the societal impact of research and innovation to build a sustainable agri-food sector. J Environ Manage 264. https://doi.org/10.1016/j.jenvman.2020.110455

Chandrakumar C, McLaren SJ, Jayamaha NP, Ramilan T (2019) Absolute sustainability-based life cycle assessment (ASLCA): a benchmarking approach to operate agri-food systems within the 2°C global carbon budget. J Ind Ecol 23:906–917. https://doi.org/10.1111/jiec.12830

Chaparro-Africano AM (2019) Toward generating sustainability indicators for agroecological markets. Agroecol Sustain Food Syst 43:40–66. https://doi.org/10.1080/21683565.2019.1566192

Colicchia C, Strozzi F (2012) Supply chain risk management: a new methodology for a systematic literature review

Conca L, Manta F, Morrone D, Toma P (2021) The impact of direct environmental, social, and governance reporting: empirical evidence in European-listed companies in the agri-food sector. Bus Strateg Environ 30:1080–1093. https://doi.org/10.1002/bse.2672

Coppola A, Ianuario S, Romano S, Viccaro M (2020) Corporate social responsibility in agri-food firms: the relationship between CSR actions and firm’s performance. AIMS Environ Sci 7:542–558. https://doi.org/10.3934/environsci.2020034

Corona B, Shen L, Reike D et al (2019) Towards sustainable development through the circular economy—a review and critical assessment on current circularity metrics. Resour Conserv Recycl 151:104498. https://doi.org/10.1016/j.resconrec.2019.104498

Correia MS (2019) Sustainability: An overview of the triple bottom line and sustainability implementation. Int J Strateg Eng 2:29–38. https://doi.org/10.4018/IJoSE.2019010103

Coteur I, Marchand F, Debruyne L, Lauwers L (2019) Structuring the myriad of sustainability assessments in agri-food systems: a case in Flanders. J Clean Prod 209:472–480. https://doi.org/10.1016/j.jclepro.2018.10.066

CREA (2020) L’agricoltura italiana conta 2019

Crenna E, Sala S, Polce C, Collina E (2017) Pollinators in life cycle assessment: towards a framework for impact assessment. J Clean Prod 140:525–536. https://doi.org/10.1016/j.jclepro.2016.02.058

D’Eusanio M, Serreli M, Zamagni A, Petti L (2018) Assessment of social dimension of a jar of honey: a methodological outline. J Clean Prod 199:503–517. https://doi.org/10.1016/j.jclepro.2018.07.157

Dania WAP, Xing K, Amer Y (2018) Collaboration behavioural factors for sustainable agri-food supply chains: a systematic review. J Clean Prod 186:851–864

De Pascale A, Arbolino R, Szopik-Depczyńska K et al (2021) A systematic review for measuring circular economy: the 61 indicators. J Clean Prod 281. https://doi.org/10.1016/j.jclepro.2020.124942

De Schoenmakere M, Gillabel J (2017) Circular by design: products in the circular economy

Del Borghi A, Gallo M, Strazza C, Del Borghi M (2014) An evaluation of environmental sustainability in the food industry through life cycle assessment: the case study of tomato products supply chain. J Clean Prod 78:121–130. https://doi.org/10.1016/j.jclepro.2014.04.083

Del Borghi A, Strazza C, Magrassi F et al (2018) Life cycle assessment for eco-design of product–package systems in the food industry—the case of legumes. Sustain Prod Consum 13:24–36. https://doi.org/10.1016/j.spc.2017.11.001

Denyer D, Tranfield D (2009) Producing a systematic review. In: Buchanan B (ed) The sage handbook of organization research methods. Sage Publications Ltd, Cornwall, pp 671–689

Google Scholar

Dietz T, Grabs J, Chong AE (2019) Mainstreamed voluntary sustainability standards and their effectiveness: evidence from the Honduran coffee sector. Regul Gov. https://doi.org/10.1111/rego.12239

Dixon-Woods M (2011) Using framework-based synthesis for conducting reviews of qualitative studies. BMC Med 9:9–10. https://doi.org/10.1186/1741-7015-9-39

do Canto NR, Bossle MB, Marques L, Dutra M, (2020) Supply chain collaboration for sustainability: a qualitative investigation of food supply chains in Brazil. Manag Environ Qual an Int J. https://doi.org/10.1108/MEQ-12-2019-0275

dos Santos RR, Guarnieri P (2020) Social gains for artisanal agroindustrial producers induced by cooperation and collaboration in agri-food supply chain. Soc Responsib J. https://doi.org/10.1108/SRJ-09-2019-0323

Doukidis GI, Matopoulos A, Vlachopoulou M, Manthou V, Manos B (2007) A conceptual framework for supply chain collaboration: empirical evidence from the agri‐food industry. Supply Chain Manag an Int Journal 12:177–186. https://doi.org/10.1108/13598540710742491

Durach CF, Kembro J, Wieland A (2017) A new paradigm for systematic literature reviews in supply chain management. J Supply Chain Manag 53:67–85. https://doi.org/10.1111/jscm.12145

Durán-Sánchez A, Álvarez-García J, Río-Rama D, De la Cruz M (2018) Sustainable water resources management: a bibliometric overview. Water 10:1–19. https://doi.org/10.3390/w10091191

Duru M, Therond O (2015) Livestock system sustainability and resilience in intensive production zones: which form of ecological modernization? Reg Environ Chang 15:1651–1665. https://doi.org/10.1007/s10113-014-0722-9

Edison Fondazione (2019) Le eccellenze agricole italiane. I primati europei e mondiali dell’Italia nei prodotti vegetali. Milan (IT)

Ehrenfeld JR (2005) The roots of sustainability. MIT Sloan Manag Rev 46(2)46:23–25

Elia V, Gnoni MG, Tornese F (2017) Measuring circular economy strategies through index methods: a critical analysis. J Clean Prod 142:2741–2751. https://doi.org/10.1016/j.jclepro.2016.10.196

Elkington J (1997) Cannibals with forks : the triple bottom line of 21st century business. Capstone, Oxford

Esposito B, Sessa MR, Sica D, Malandrino O (2020) Towards circular economy in the agri-food sector. A systematic literature review. Sustain 12. https://doi.org/10.3390/SU12187401

European Commission (2018) Agri-food trade in 2018

European Commission (2019) Monitoring EU agri-food trade: development until September 2019

Eurostat (2018) Small and large farms in the EU - statistics from the farm structure survey

FAO (2011) Biodiversity for food and agriculture. Italy, Rome

FAO (2012) Energy-smart food at FAO: an overview. Italy, Rome

FAO (2014) Food wastage footprint: fool cost-accounting

FAO (2016) The state of food and agriculture climate change, agriculture and food security. Italy, Rome

FAO (2017) The future of food and agriculture: trends and challenges. Italy, Rome

FAO (2020) The state of food security and nutrition in the world. Transforming Food Systems for Affordable Healthy Diets. Rome, Italy

Fassio F, Tecco N (2019) Circular economy for food: a systemic interpretation of 40 case histories in the food system in their relationships with SDGs. Systems 7:43. https://doi.org/10.3390/systems7030043

Fathollahi A, Coupe SJ (2021) Life cycle assessment (LCA) and life cycle costing (LCC) of road drainage systems for sustainability evaluation: quantifying the contribution of different life cycle phases. Sci Total Environ 776:145937. https://doi.org/10.1016/j.scitotenv.2021.145937

Ferreira VJ, Arnal ÁJ, Royo P et al (2019) Energy and resource efficiency of electroporation-assisted extraction as an emerging technology towards a sustainable bio-economy in the agri-food sector. J Clean Prod 233:1123–1132. https://doi.org/10.1016/j.jclepro.2019.06.030

Fiksel J (2006) A framework for sustainable remediation. JOM 8:15–22. https://doi.org/10.1021/es202595w

Flick U (2014) An introduction to qualitative research

Franciosi C, Voisin A, Miranda S et al (2020) Measuring maintenance impacts on sustainability of manufacturing industries : from a systematic literature review to a framework proposal. J Clean Prod 260:1–19. https://doi.org/10.1016/j.jclepro.2020.121065

Gaitán-Cremaschi D, Meuwissen MPM, Oude AGJML (2017) Total factor productivity: a framework for measuring agri-food supply chain performance towards sustainability. Appl Econ Perspect Policy 39:259–285. https://doi.org/10.1093/aepp/ppw008

Galdeano-Gómez E, Zepeda-Zepeda JA, Piedra-Muñoz L, Vega-López LL (2017) Family farm’s features influencing socio-economic sustainability: an analysis of the agri-food sector in southeast Spain. New Medit 16:50–61

Gallopín G, Herrero LMJ, Rocuts A (2014) Conceptual frameworks and visual interpretations of sustainability. Int J Sustain Dev 17:298–326. https://doi.org/10.1504/IJSD.2014.064183

Gallopín GC (2003) Sostenibilidad y desarrollo sostenible: un enfoque sistémico. Cepal, LATIN AMERICA

Garnett T (2013) Food sustainability: problems, perspectives and solutions. Proc Nutr Soc 72:29–39. https://doi.org/10.1017/S0029665112002947

Garofalo P, D’Andrea L, Tomaiuolo M et al (2017) Environmental sustainability of agri-food supply chains in Italy: the case of the whole-peeled tomato production under life cycle assessment methodology. J Food Eng 200:1–12. https://doi.org/10.1016/j.jfoodeng.2016.12.007

Gava O, Bartolini F, Venturi F et al (2018) A reflection of the use of the life cycle assessment tool for agri-food sustainability. Sustain 11. https://doi.org/10.3390/su11010071

Gazzola P, Querci E (2017) The connection between the quality of life and sustainable ecological development. Eur Sci J 7881:1857–7431

Geissdoerfer M, Savaget P, Bocken N, Hultink EJ (2017) The circular economy – a new sustainability paradigm ? The circular economy – a new sustainability paradigm ? J Clean Prod 143:757–768. https://doi.org/10.1016/j.jclepro.2016.12.048

Georgescu-Roegen N (1971) The entropy low and the economic process. Harward University Press, Cambridge Mass

Book Google Scholar

Gerbens-Leenes PW, Moll HC, Schoot Uiterkamp AJM (2003) Design and development of a measuring method for environmental sustainability in food production systems. Ecol Econ 46:231–248. https://doi.org/10.1016/S0921-8009(03)00140-X

Gésan-Guiziou G, Alaphilippe A, Aubin J et al (2020) Diversity and potentiality of multi-criteria decision analysis methods for agri-food research. Agron Sustain Dev 40. https://doi.org/10.1007/s13593-020-00650-3

Ghisellini P, Cialani C, Ulgiati S (2016) A review on circular economy: the expected transition to a balanced interplay of environmental and economic systems. J Clean Prod 114:11–32. https://doi.org/10.1016/j.jclepro.2015.09.007

Godoy-Durán Á, Galdeano- Gómez E, Pérez-Mesa JC, Piedra-Muñoz L (2017) Assessing eco-efficiency and the determinants of horticultural family-farming in southeast Spain. J Environ Manage 204:594–604. https://doi.org/10.1016/j.jenvman.2017.09.037

Gold S, Kunz N, Reiner G (2017) Sustainable global agrifood supply chains: exploring the barriers. J Ind Ecol 21:249–260. https://doi.org/10.1111/jiec.12440

Goucher L, Bruce R, Cameron DD et al (2017) The environmental impact of fertilizer embodied in a wheat-to-bread supply chain. Nat Plants 3:1–5. https://doi.org/10.1038/nplants.2017.12

Green A, Nemecek T, Chaudhary A, Mathys A (2020) Assessing nutritional, health, and environmental sustainability dimensions of agri-food production. Glob Food Sec 26:100406. https://doi.org/10.1016/j.gfs.2020.100406

Guinée JB, Heijungs R, Huppes G et al (2011) Life cycle assessment: past, present, and future †. Environ Sci Technol 45:90–96. https://doi.org/10.1021/es101316v

Guiomar N, Godinho S, Pinto-Correia T et al (2018) Typology and distribution of small farms in Europe: towards a better picture. Land Use Policy 75:784–798. https://doi.org/10.1016/j.landusepol.2018.04.012

Gunasekaran A, Patel C, McGaughey RE (2004) A framework for supply chain performance measurement. Int J Prod Econ 87:333–347. https://doi.org/10.1016/j.ijpe.2003.08.003

Gunasekaran A, Patel C, Tirtiroglu E (2001) Performance measures and metrics in a supply chain environment. Int J Oper Prod Manag 21:71–87. https://doi.org/10.1108/01443570110358468

Hamam M, Chinnici G, Di Vita G et al (2021) Circular economy models in agro-food systems: a review. Sustain 13

Harun SN, Hanafiah MM, Aziz NIHA (2021) An LCA-based environmental performance of rice production for developing a sustainable agri-food system in Malaysia. Environ Manage 67:146–161. https://doi.org/10.1007/s00267-020-01365-7

Harvey M, Pilgrim S (2011) The new competition for land: food, energy, and climate change. Food Policy 36:S40–S51. https://doi.org/10.1016/j.foodpol.2010.11.009

Hawkes C, Ruel MT (2006) Understanding the links between agriculture and health. DC: International Food Policy Research Institute. Washington, USA

Hellweg S, Milà i Canals L (2014) Emerging approaches, challenges and opportunities in life cycle assessment. Science (80)344:1109LP–1113. https://doi.org/10.1126/science.1248361

Higgins V, Dibden J, Cocklin C (2015) Private agri-food governance and greenhouse gas abatement: constructing a corporate carbon economy. Geoforum 66:75–84. https://doi.org/10.1016/j.geoforum.2015.09.012

Hill T (1995) Manufacturing strategy: text and cases., Macmillan

Hjeresen DD, Gonzales R (2020) Green chemistry promote sustainable agriculture?The rewards are higher yields and less environmental contamination. Environemental Sci Techonology 103–107

Horne R, Grant T, Verghese K (2009) Life cycle assessment: principles, practice, and prospects. Csiro Publishing, Collingwood, Australia

Horton P, Koh L, Guang VS (2016) An integrated theoretical framework to enhance resource efficiency, sustainability and human health in agri-food systems. J Clean Prod 120:164–169. https://doi.org/10.1016/j.jclepro.2015.08.092

Hospido A, Davis J, Berlin J, Sonesson U (2010) A review of methodological issues affecting LCA of novel food products. Int J Life Cycle Assess 15:44–52. https://doi.org/10.1007/s11367-009-0130-4

Huffman T, Liu J, Green M et al (2015) Improving and evaluating the soil cover indicator for agricultural land in Canada. Ecol Indic 48:272–281. https://doi.org/10.1016/j.ecolind.2014.07.008

Ilbery B, Maye D (2005) Food supply chains and sustainability: evidence from specialist food producers in the Scottish/English borders. Land Use Policy 22:331–344. https://doi.org/10.1016/j.landusepol.2004.06.002

Ingrao C, Faccilongo N, Valenti F et al (2019) Tomato puree in the Mediterranean region: an environmental life cycle assessment, based upon data surveyed at the supply chain level. J Clean Prod 233:292–313. https://doi.org/10.1016/j.jclepro.2019.06.056

Iocola I, Angevin F, Bockstaller C et al (2020) An actor-oriented multi-criteria assessment framework to support a transition towards sustainable agricultural systems based on crop diversification. Sustain 12. https://doi.org/10.3390/su12135434

Irabien A, Darton RC (2016) Energy–water–food nexus in the Spanish greenhouse tomato production. Clean Technol Environ Policy 18:1307–1316. https://doi.org/10.1007/s10098-015-1076-9

ISO 14040:2006 (2006) Environmental management — life cycle assessment — principles and framework

ISO 14044:2006 (2006) Environmental management — life cycle assessment — requirements and guidelines

ISO 15392:2008 (2008) Sustainability in building construction–general principles

Istat (2019) Andamento dell’economia agricola

Jaakkola E (2020) Designing conceptual articles : four approaches. AMS Rev 1–9. https://doi.org/10.1007/s13162-020-00161-0

Jin R, Yuan H, Chen Q (2019) Science mapping approach to assisting the review of construction and demolition waste management research published between 2009 and 2018. Resour Conserv Recycl 140:175–188. https://doi.org/10.1016/j.resconrec.2018.09.029

Johnston P, Everard M, Santillo D, Robèrt KH (2007) Reclaiming the definition of sustainability. Environ Sci Pollut Res Int 14:60–66. https://doi.org/10.1065/espr2007.01.375

Jorgensen SE, Burkhard B, Müller F (2013) Twenty volumes of ecological indicators-an accounting short review. Ecol Indic 28:4–9. https://doi.org/10.1016/j.ecolind.2012.12.018

Joshi S, Sharma M, Kler R (2020) Modeling circular economy dimensions in agri-tourism clusters: sustainable performance and future research directions. Int J Math Eng Manag Sci 5:1046–1061. https://doi.org/10.33889/IJMEMS.2020.5.6.080

Kamilaris A, Gao F, Prenafeta-Boldu FX, Ali MI (2017) Agri-IoT: a semantic framework for Internet of Things-enabled smart farming applications. In: 2016 IEEE 3rd World Forum on Internet of Things, WF-IoT 2016. pp 442–447

Karuppusami G, Gandhinathan R (2006) Pareto analysis of critical success factors of total quality management: a literature review and analysis. TQM Mag 18:372–385. https://doi.org/10.1108/09544780610671048

Kates RW, Parris TM, Leiserowitz AA (2005) What is sustainable development? Goals, indicators, values, and practice. Environ Sci Policy Sustain Dev 47:8–21. https://doi.org/10.1080/00139157.2005.10524444

Khounani Z, Hosseinzadeh-Bandbafha H, Moustakas K et al (2021) Environmental life cycle assessment of different biorefinery platforms valorizing olive wastes to biofuel, phosphate salts, natural antioxidant, and an oxygenated fuel additive (triacetin). J Clean Prod 278:123916. https://doi.org/10.1016/j.jclepro.2020.123916

Kitchenham B, Charters S (2007) Guidelines for performing systematic literature reviews in software engineering version 2.3. Engineering 45. https://doi.org/10.1145/1134285.1134500

Korhonen J, Nuur C, Feldmann A, Birkie SE (2018) Circular economy as an essentially contested concept. J Clean Prod 175:544–552. https://doi.org/10.1016/j.jclepro.2017.12.111

Kuisma M, Kahiluoto H (2017) Biotic resource loss beyond food waste: agriculture leaks worst. Resour Conserv Recycl 124:129–140. https://doi.org/10.1016/j.resconrec.2017.04.008

Laso J, Hoehn D, Margallo M et al (2018) Assessing energy and environmental efficiency of the Spanish agri-food system using the LCA/DEA methodology. Energies 11. https://doi.org/10.3390/en11123395

Lee KM (2007) So What is the “triple bottom line”? Int J Divers Organ Communities Nations Annu Rev 6:67–72. https://doi.org/10.18848/1447-9532/cgp/v06i06/39283

Lehmann RJ, Hermansen JE, Fritz M et al (2011) Information services for European pork chains - closing gaps in information infrastructures. Comput Electron Agric 79:125–136. https://doi.org/10.1016/j.compag.2011.09.002

León-Bravo V, Caniato F, Caridi M, Johnsen T (2017) Collaboration for sustainability in the food supply chain: a multi-stage study in Italy. Sustainability 9:1253

Lepage A (2009) The quality of life as attribute of sustainability. TQM J 21:105–115. https://doi.org/10.1108/17542730910938119

Li CZ, Zhao Y, Xiao B et al (2020) Research trend of the application of information technologies in construction and demolition waste management. J Clean Prod 263. https://doi.org/10.1016/j.jclepro.2020.121458

Lo Giudice A, Mbohwa C, Clasadonte MT, Ingrao C (2014) Life cycle assessment interpretation and improvement of the Sicilian artichokes production. Int J Environ Res 8:305–316. https://doi.org/10.22059/ijer.2014.721

Lueddeckens S, Saling P, Guenther E (2020) Temporal issues in life cycle assessment—a systematic review. Int J Life Cycle Assess 25:1385–1401. https://doi.org/10.1007/s11367-020-01757-1

Luo J, Ji C, Qiu C, Jia F (2018) Agri-food supply chain management: bibliometric and content analyses. Sustain 10. https://doi.org/10.3390/su10051573

Lynch J, Donnellan T, Finn JA et al (2019) Potential development of Irish agricultural sustainability indicators for current and future policy evaluation needs. J Environ Manage 230:434–445. https://doi.org/10.1016/j.jenvman.2018.09.070

MacArthur E (2013) Towards the circular economy. J Ind Ecol 2:23–44

MacArthur E (2017) Delivering the circular economy a toolkit for policymakers, The Ellen MacArthur Foundation

MacInnis DJ (2011) A framework for conceptual. J Mark 75:136–154. https://doi.org/10.1509/jmkg.75.4.136

Mangla SK, Luthra S, Rich N et al (2018) Enablers to implement sustainable initiatives in agri-food supply chains. Int J Prod Econ 203:379–393. https://doi.org/10.1016/j.ijpe.2018.07.012

Marotta G, Nazzaro C, Stanco M (2017) How the social responsibility creates value: models of innovation in Italian pasta industry. Int J Glob Small Bus 9:144–167. https://doi.org/10.1504/IJGSB.2017.088923

Martucci O, Arcese G, Montauti C, Acampora A (2019) Social aspects in the wine sector: comparison between social life cycle assessment and VIVA sustainable wine project indicators. Resources 8. https://doi.org/10.3390/resources8020069

Mayring P (2004) Forum : Qualitative social research Sozialforschung 2. History of content analysis. A Companion to Qual Res 1:159–176

McKelvey B (2002) Managing coevolutionary dynamics. In: 18th EGOS Conference. Barcelona, Spain, pp 1–21

McMichael AJ, Butler CD, Folke C (2003) New visions for addressing sustainability. Science (80- ) 302:1191–1920

Mehmood A, Ahmed S, Viza E et al (2021) Drivers and barriers towards circular economy in agri-food supply chain: a review. Bus Strateg Dev 1–17. https://doi.org/10.1002/bsd2.171

Mella P, Gazzola P (2011) Sustainability and quality of life: the development model. In: Kapounek S (ed) Enterprise and competitive environment. Mendel University: Brno, Czechia. 542–551

Merli R, Preziosi M, Acampora A (2018) How do scholars approach the circular economy ? A systematic literature review. J Clean Prod 178:703–722. https://doi.org/10.1016/j.jclepro.2017.12.112

Merli R, Preziosi M, Acampora A et al (2020) Recycled fibers in reinforced concrete: a systematic literature review. J Clean Prod 248:119207. https://doi.org/10.1016/j.jclepro.2019.119207

Miglietta PP, Morrone D (2018) Managing water sustainability: virtual water flows and economic water productivity assessment of the wine trade between Italy and the Balkans. Sustain 10. https://doi.org/10.3390/su10020543

Mitchell MGE, Chan KMA, Newlands NK, Ramankutty N (2020) Spatial correlations don’t predict changes in agricultural ecosystem services: a Canada-wide case study. Front Sustain Food Syst 4:1–17. https://doi.org/10.3389/fsufs.2020.539892

Moraga G, Huysveld S, Mathieux F et al (2019) Circular economy indicators: what do they measure?. Resour Conserv Recycl 146:452–461. https://doi.org/10.1016/j.resconrec.2019.03.045

Morrissey JE, Dunphy NP (2015) Towards sustainable agri-food systems: the role of integrated sustainability and value assessment across the supply-chain. Int J Soc Ecol Sustain Dev 6:41–58. https://doi.org/10.4018/IJSESD.2015070104

Moser G (2009) Quality of life and sustainability: toward person-environment congruity. J Environ Psychol 29:351–357. https://doi.org/10.1016/j.jenvp.2009.02.002

Muijs D (2010) Doing quantitative research in education with SPSS. London

Muller MF, Esmanioto F, Huber N, Loures ER (2019) A systematic literature review of interoperability in the green Building Information Modeling lifecycle. J Clean Prod 223:397–412. https://doi.org/10.1016/j.jclepro.2019.03.114

Muradin M, Joachimiak-Lechman K, Foltynowicz Z (2018) Evaluation of eco-efficiency of two alternative agricultural biogas plants. Appl Sci 8. https://doi.org/10.3390/app8112083

Naseer MA, ur R, Ashfaq M, Hassan S, et al (2019) Critical issues at the upstream level in sustainable supply chain management of agri-food industries: evidence from Pakistan’s citrus industry. Sustain 11:1–19. https://doi.org/10.3390/su11051326

Nattassha R, Handayati Y, Simatupang TM, Siallagan M (2020) Understanding circular economy implementation in the agri-food supply chain: the case of an Indonesian organic fertiliser producer. Agric Food Secur 9:1–16. https://doi.org/10.1186/s40066-020-00264-8

Nazari-Sharabian M, Ahmad S, Karakouzian M (2018) Climate change and eutrophication: a short review. Eng Technol Appl Sci Res 8:3668–3672. https://doi.org/10.5281/zenodo.2532694

Nazir N (2017) Understanding life cycle thinking and its practical application to agri-food system. Int J Adv Sci Eng Inf Technol 7:1861–1870. https://doi.org/10.18517/ijaseit.7.5.3578

Negra C, Remans R, Attwood S et al (2020) Sustainable agri-food investments require multi-sector co-development of decision tools. Ecol Indic 110:105851. https://doi.org/10.1016/j.ecolind.2019.105851

Newsham KK, Robinson SA (2009) Responses of plants in polar regions to UVB exposure: a meta-analysis. Glob Chang Biol 15:2574–2589. https://doi.org/10.1111/j.1365-2486.2009.01944.x

Niemeijer D, de Groot RS (2008) A conceptual framework for selecting environmental indicator sets. Ecol Indic 8:14–25. https://doi.org/10.1016/j.ecolind.2006.11.012

Niero M, Kalbar PP (2019) Coupling material circularity indicators and life cycle based indicators: a proposal to advance the assessment of circular economy strategies at the product level. Resour Conserv Recycl 140:305–312. https://doi.org/10.1016/j.resconrec.2018.10.002

Nikolaou IE, Tsagarakis KP (2021) An introduction to circular economy and sustainability: some existing lessons and future directions. Sustain Prod Consum 28:600–609. https://doi.org/10.1016/j.spc.2021.06.017

Notarnicola B, Hayashi K, Curran MA, Huisingh D (2012) Progress in working towards a more sustainable agri-food industry. J Clean Prod 28:1–8. https://doi.org/10.1016/j.jclepro.2012.02.007

Notarnicola B, Tassielli G, Renzulli PA, Monforti F (2017) Energy flows and greenhouses gases of EU (European Union) national breads using an LCA (life cycle assessment) approach. J Clean Prod 140:455–469. https://doi.org/10.1016/j.jclepro.2016.05.150

Opferkuch K, Caeiro S, Salomone R, Ramos TB (2021) Circular economy in corporate sustainability reporting: a review of organisational approaches. Bus Strateg Environ 1–22. https://doi.org/10.1002/bse.2854

Padilla-Rivera A, do Carmo BBT, Arcese G, Merveille N, (2021) Social circular economy indicators: selection through fuzzy delphi method. Sustain Prod Consum 26:101–110. https://doi.org/10.1016/j.spc.2020.09.015

Pagotto M, Halog A (2016) Towards a circular economy in Australian agri-food industry: an application of input-output oriented approaches for analyzing resource efficiency and competitiveness potential. J Ind Ecol 20:1176–1186. https://doi.org/10.1111/jiec.12373

Parent G, Lavallée S (2011) LCA potentials and limits within a sustainable agri-food statutory framework. Global food insecurity. Springer, Netherlands, Dordrecht, pp 161–171

Chapter Google Scholar

Pattey E, Qiu G (2012) Trends in primary particulate matter emissions from Canadian agriculture. J Air Waste Manag Assoc 62:737–747. https://doi.org/10.1080/10962247.2012.672058

Pauliuk S (2018) Critical appraisal of the circular economy standard BS 8001:2017 and a dashboard of quantitative system indicators for its implementation in organizations. Resour Conserv Recycl 129:81–92. https://doi.org/10.1016/j.resconrec.2017.10.019

Peano C, Migliorini P, Sottile F (2014) A methodology for the sustainability assessment of agri-food systems: an application to the slow food presidia project. Ecol Soc 19. https://doi.org/10.5751/ES-06972-190424

Peano C, Tecco N, Dansero E et al (2015) Evaluating the sustainability in complex agri-food systems: the SAEMETH framework. Sustain 7:6721–6741. https://doi.org/10.3390/su7066721

Pearce DW, Turner RK (1990) Economics of natural resources and the environment. Harvester Wheatsheaf, Hemel Hempstead, Herts

Pelletier N (2018) Social sustainability assessment of Canadian egg production facilities: methods, analysis, and recommendations. Sustain 10:1–17. https://doi.org/10.3390/su10051601

Peña C, Civit B, Gallego-Schmid A et al (2021) Using life cycle assessment to achieve a circular economy. Int J Life Cycle Assess 26:215–220. https://doi.org/10.1007/s11367-020-01856-z

Perez Neira D (2016) Energy sustainability of Ecuadorian cacao export and its contribution to climate change. A case study through product life cycle assessment. J Clean Prod 112:2560–2568. https://doi.org/10.1016/j.jclepro.2015.11.003

Pérez-Neira D, Grollmus-Venegas A (2018) Life-cycle energy assessment and carbon footprint of peri-urban horticulture. A comparative case study of local food systems in Spain. Landsc Urban Plan 172:60–68. https://doi.org/10.1016/j.landurbplan.2018.01.001

Pérez-Pons ME, Plaza-Hernández M, Alonso RS et al (2021) Increasing profitability and monitoring environmental performance: a case study in the agri-food industry through an edge-iot platform. Sustain 13:1–16. https://doi.org/10.3390/su13010283

Petti L, Serreli M, Di Cesare S (2018) Systematic literature review in social life cycle assessment. Int J Life Cycle Assess 23:422–431. https://doi.org/10.1007/s11367-016-1135-4

Pieroni MPP, McAloone TC, Pigosso DCA (2019) Business model innovation for circular economy and sustainability: a review of approaches. J Clean Prod 215:198–216. https://doi.org/10.1016/j.jclepro.2019.01.036

Polit DF, Beck CT (2004) Nursing research: principles and methods. Lippincott Williams & Wilkins, Philadelphia, PA

Porkka M, Gerten D, Schaphoff S et al (2016) Causes and trends of water scarcity in food production. Environ Res Lett 11:015001. https://doi.org/10.1088/1748-9326/11/1/015001

Prajapati H, Kant R, Shankar R (2019) Bequeath life to death: state-of-art review on reverse logistics. J Clean Prod 211:503–520. https://doi.org/10.1016/j.jclepro.2018.11.187

Priyadarshini P, Abhilash PC (2020) Policy recommendations for enabling transition towards sustainable agriculture in India. Land Use Policy 96:104718. https://doi.org/10.1016/j.landusepol.2020.104718

Pronti A, Coccia M (2020) Multicriteria analysis of the sustainability performance between agroecological and conventional coffee farms in the East Region of Minas Gerais (Brazil). Renew Agric Food Syst. https://doi.org/10.1017/S1742170520000332

Rabadán A, González-Moreno A, Sáez-Martínez FJ (2019) Improving firms’ performance and sustainability: the case of eco-innovation in the agri-food industry. Sustain 11. https://doi.org/10.3390/su11205590

Raut RD, Luthra S, Narkhede BE et al (2019) Examining the performance oriented indicators for implementing green management practices in the Indian agro sector. J Clean Prod 215:926–943. https://doi.org/10.1016/j.jclepro.2019.01.139

Recanati F, Marveggio D, Dotelli G (2018) From beans to bar: a life cycle assessment towards sustainable chocolate supply chain. Sci Total Environ 613–614:1013–1023. https://doi.org/10.1016/j.scitotenv.2017.09.187

Redclift M (2005) Sustainable development (1987–2005): an oxymoron comes of age. Sustain Dev 13:212–227. https://doi.org/10.1002/sd.281

Rezaei M, Soheilifard F, Keshvari A (2021) Impact of agrochemical emission models on the environmental assessment of paddy rice production using life cycle assessment approach. Energy Sources. Part A Recover Util Environ Eff 1–16

Rigamonti L, Mancini E (2021) Life cycle assessment and circularity indicators. Int J Life Cycle Assess. https://doi.org/10.1007/s11367-021-01966-2

Risku-Norja H, Mäenpää I (2007) MFA model to assess economic and environmental consequences of food production and consumption. Ecol Econ 60:700–711. https://doi.org/10.1016/j.ecolecon.2006.05.001

Ritzén S, Sandström GÖ (2017) Barriers to the circular economy – integration of perspectives and domains. Procedia CIRP 64:7–12. https://doi.org/10.1016/j.procir.2017.03.005

Rockström J, Steffen W, Noone K et al (2009) A safe operating space for humanity. Nature 461:472–475. https://doi.org/10.1038/461472a

Roos Lindgreen E, Mondello G, Salomone R et al (2021) Exploring the effectiveness of grey literature indicators and life cycle assessment in assessing circular economy at the micro level: a comparative analysis. Int J Life Cycle Assess. https://doi.org/10.1007/s11367-021-01972-4

Roselli L, Casieri A, De Gennaro BC et al (2020) Environmental and economic sustainability of table grape production in Italy. Sustain 12. https://doi.org/10.3390/su12093670

Ross RB, Pandey V, Ross KL (2015) Sustainability and strategy in U.S. agri-food firms: an assessment of current practices. Int Food Agribus Manag Rev 18:17–48

Royo P, Ferreira VJ, López-Sabirón AM, Ferreira G. (2016) Hybrid diagnosis to characterise the energy and environmental enhancement of photovoltaic modules using smart materials. Energy 101:174–189. https://doi.org/10.1016/j.energy.2016.01.101

Ruggerio CA (2021) Sustainability and sustainable development: a review of principles and definitions. Sci Total Environ 786:147481. https://doi.org/10.1016/j.scitotenv.2021.147481

Ruiz-Almeida A, Rivera-Ferre MG (2019) Internationally-based indicators to measure agri-food systems sustainability using food sovereignty as a conceptual framework. Food Secur 11:1321–1337. https://doi.org/10.1007/s12571-019-00964-5

Ryan M, Hennessy T, Buckley C et al (2016) Developing farm-level sustainability indicators for Ireland using the Teagasc National Farm Survey. Irish J Agric Food Res 55:112–125. https://doi.org/10.1515/ijafr-2016-0011

Saade MRM, Yahia A, Amor B (2020) How has LCA been applied to 3D printing ? A systematic literature review and recommendations for future studies. J Clean Prod 244:118803. https://doi.org/10.1016/j.jclepro.2019.118803

Saitone TL, Sexton RJ (2017) Agri-food supply chain: evolution and performance with conflicting consumer and societal demands. Eur Rev Agric Econ 44:634–657. https://doi.org/10.1093/erae/jbx003

Salim N, Ab Rahman MN, Abd Wahab D (2019) A systematic literature review of internal capabilities for enhancing eco-innovation performance of manufacturing firms. J Clean Prod 209:1445–1460. https://doi.org/10.1016/j.jclepro.2018.11.105

Salimi N (2021) Circular economy in agri-food systems BT - strategic decision making for sustainable management of industrial networks. In: International S (ed) Rezaei J. Publishing, Cham, pp 57–70

Salomone R, Ioppolo G (2012) Environmental impacts of olive oil production: a life cycle assessment case study in the province of Messina (Sicily). J Clean Prod 28:88–100. https://doi.org/10.1016/j.jclepro.2011.10.004

Sánchez AD, Río DMDLC, García JÁ (2017) Bibliometric analysis of publications on wine tourism in the databases Scopus and WoS. Eur Res Manag Bus Econ 23:8–15. https://doi.org/10.1016/j.iedeen.2016.02.001

Saputri VHL, Sutopo W, Hisjam M, Ma’aram A (2019) Sustainable agri-food supply chain performance measurement model for GMO and non-GMO using data envelopment analysis method. Appl Sci 9. https://doi.org/10.3390/app9061199

Sassanelli C, Rosa P, Rocca R, Terzi S (2019) Circular economy performance assessment methods : a systematic literature review. J Clean Prod 229:440–453. https://doi.org/10.1016/j.jclepro.2019.05.019

Schiefer S, Gonzalez C, Flanigan S (2015) More than just a factor in transition processes? The role of collaboration in agriculture. In: Sutherland LA, Darnhofer I, Wilson GA, Zagata L (eds) Transition pathways towards sustainability in agriculture: case studies from Europe, CPI Group. Croydon, UK, pp. 83

Seuring S, Muller M (2008) From a literature review to a conceptual framework for sustainable supply chain management. J Clean Prod 16:1699–1710. https://doi.org/10.1016/j.jclepro.2008.04.020

Silvestri C, Silvestri L, Forcina A, et al (2021) Green chemistry contribution towards more equitable global sustainability and greater circular economy: A systematic literature review. J Clean Prod 294. https://doi.org/10.1016/j.jclepro.2021.126137

Smetana S, Schmitt E, Mathys A (2019) Sustainable use of Hermetia illucens insect biomass for feed and food: attributional and consequential life cycle assessment. Resour Conserv Recycl 144:285–296. https://doi.org/10.1016/j.resconrec.2019.01.042

Sonesson U, Berlin J, Ziegler F (2010) Environmental assessment and management in the food industry: life cycle assessment and related approaches. Woodhead Publishing, Cambridge

Soussana JF (2014) Research priorities for sustainable agri-food systems and life cycle assessment. J Clean Prod 73:19–23. https://doi.org/10.1016/j.jclepro.2014.02.061

Soylu A, Oruç C, Turkay M et al (2006) Synergy analysis of collaborative supply chain management in energy systems using multi-period MILP. Eur J Oper Res 174:387–403. https://doi.org/10.1016/j.ejor.2005.02.042

Spaiser V, Ranganathan S, Swain RB, Sumpter DJ (2017) The sustainable development oxymoron: quantifying and modelling the incompatibility of sustainable development goals. Int J Sustain Dev World Ecol 24:457–470. https://doi.org/10.1080/13504509.2016.1235624

Stewart R, Niero M (2018) Circular economy in corporate sustainability strategies: a review of corporate sustainability reports in the fast-moving consumer goods sector. Bus Strateg Environ 27:1005–1022. https://doi.org/10.1002/bse.2048

Stillitano T, Spada E, Iofrida N et al (2021) Sustainable agri-food processes and circular economy pathways in a life cycle perspective: state of the art of applicative research. Sustain 13:1–29. https://doi.org/10.3390/su13052472

Stone J, Rahimifard S (2018) Resilience in agri-food supply chains: a critical analysis of the literature and synthesis of a novel framework. Supply Chain Manag 23:207–238. https://doi.org/10.1108/SCM-06-2017-0201

Strazza C, Del Borghi A, Gallo M, Del Borghi M (2011) Resource productivity enhancement as means for promoting cleaner production: analysis of co-incineration in cement plants through a life cycle approach. J Clean Prod 19:1615–1621. https://doi.org/10.1016/j.jclepro.2011.05.014

Su B, Heshmati A, Geng Y, Yu X (2013) A review of the circular economy in China: moving from rhetoric to implementation. J Clean Prod 42:215–227. https://doi.org/10.1016/j.jclepro.2012.11.020

Suárez-Eiroa B, Fernández E, Méndez-Martínez G, Soto-Oñate D (2019) Operational principles of circular economy for sustainable development: linking theory and practice. J Clean Prod 214:952–961. https://doi.org/10.1016/j.jclepro.2018.12.271

Svensson G, Wagner B (2015) Implementing and managing economic, social and environmental efforts of business sustainability. Manag Environ Qual an Int Journal 26:195–213. https://doi.org/10.1108/MEQ-09-2013-0099

Tasca AL, Nessi S, Rigamonti L (2017) Environmental sustainability of agri-food supply chains: an LCA comparison between two alternative forms of production and distribution of endive in northern Italy. J Clean Prod 140:725–741. https://doi.org/10.1016/j.jclepro.2016.06.170

Tassielli G, Notarnicola B, Renzulli PA, Arcese G (2018) Environmental life cycle assessment of fresh and processed sweet cherries in southern Italy. J Clean Prod 171:184–197. https://doi.org/10.1016/j.jclepro.2017.09.227

Teixeira R, Pax S (2011) A survey of life cycle assessment practitioners with a focus on the agri-food sector. J Ind Ecol 15:817–820. https://doi.org/10.1111/j.1530-9290.2011.00421.x

Tobergte DR, Curtis S (2013) ILCD Handbook. J Chem Info Model. https://doi.org/10.278/33030

Tortorella MM, Di Leo S, Cosmi C et al (2020) A methodological integrated approach to analyse climate change effects in agri-food sector: the TIMES water-energy-food module. Int J Environ Res Public Health 17:1–21. https://doi.org/10.3390/ijerph17217703

Tranfield D, Denyer D, Smart P (2003) Towards a methodology for developing evidenceinformed management knowledge by means of systematic review. Br J Manag 14:207–222

Trivellas P, Malindretos G, Reklitis P (2020) Implications of green logistics management on sustainable business and supply chain performance: evidence from a survey in the greek agri-food sector. Sustain 12:1–29. https://doi.org/10.3390/su122410515

Tsangas M, Gavriel I, Doula M et al (2020) Life cycle analysis in the framework of agricultural strategic development planning in the Balkan region. Sustain 12:1–15. https://doi.org/10.3390/su12051813

Ülgen VS, Björklund M, Simm N (2019) Inter-organizational supply chain interaction for sustainability : a systematic literature review.

UNEP S (2020) Guidelines for social life cycle assessment of products and organizations 2020.

UNEP/SETAC (2009) United Nations Environment Programme-society of Environmental Toxicology and Chemistry. Guidelines for social life cycle assessment of products. France

United Nations (2011) Guiding principles on business and human rights. Implementing the United Nations “protect, respect and remedy” framework

United Nations (2015) Transforming our world: the 2030 agenda for sustainable development. sustainabledevelopment.un.org

Van Asselt ED, Van Bussel LGJ, Van Der Voet H et al (2014) A protocol for evaluating the sustainability of agri-food production systems - a case study on potato production in peri-urban agriculture in the Netherlands. Ecol Indic 43:315–321. https://doi.org/10.1016/j.ecolind.2014.02.027

Van der Ploeg JD (2014) Peasant-driven agricultural growth and food sovereignty. J Peasant Stud 41:999–1030. https://doi.org/10.1080/03066150.2013.876997

van Eck NJ, Waltman L (2010) Software survey: VOSviewer, a computer program for bibliometric mapping. Scientometrics 84:523–538. https://doi.org/10.1007/s11192-009-0146-3

Van Eck NJ, Waltman L (2019) Manual for VOSviwer version 1.6.10. CWTS Meaningful metrics 1–53

Vasa L, Angeloska A, Trendov NM (2017) Comparative analysis of circular agriculture development in selected Western Balkan countries based on sustainable performance indicators. Econ Ann 168:44–47. https://doi.org/10.21003/ea.V168-09

Verdecho MJ, Alarcón-Valero F, Pérez-Perales D et al (2020) A methodology to select suppliers to increase sustainability within supply chains. Cent Eur J Oper Res. https://doi.org/10.1007/s10100-019-00668-3

Vergine P, Salerno C, Libutti A et al (2017) Closing the water cycle in the agro-industrial sector by reusing treated wastewater for irrigation. J Clean Prod 164:587–596. https://doi.org/10.1016/j.jclepro.2017.06.239

WCED (1987) Our common future - call for action

Webster K (2013) What might we say about a circular economy? Some temptations to avoid if possible. World Futures 69:542–554

Wheaton E, Kulshreshtha S (2013) Agriculture and climate change: implications for environmental sustainability indicators. WIT Trans Ecol Environ 175:99–110. https://doi.org/10.2495/ECO130091

Wijewickrama MKCS, Chileshe N, Rameezdeen R, Ochoa JJ (2021) Information sharing in reverse logistics supply chain of demolition waste: a systematic literature review. J Clean Prod 280:124359. https://doi.org/10.1016/j.jclepro.2020.124359

Woodhouse A, Davis J, Pénicaud C, Östergren K (2018) Sustainability checklist in support of the design of food processing. Sustain Prod Consum 16:110–120. https://doi.org/10.1016/j.spc.2018.06.008

Wu R, Yang D, Chen J (2014) Social Life Cycle Assessment Revisited Sustain 6:4200–4226. https://doi.org/10.3390/su6074200

Yadav S, Luthra S, Garg D (2021) Modelling Internet of things (IoT)-driven global sustainability in multi-tier agri-food supply chain under natural epidemic outbreaks. Environ Sci Pollut Res 16633–16654. https://doi.org/10.1007/s11356-020-11676-1

Yee FM, Shaharudin MR, Ma G et al (2021) Green purchasing capabilities and practices towards Firm’s triple bottom line in Malaysia. J Clean Prod 307:127268. https://doi.org/10.1016/j.jclepro.2021.127268

Yigitcanlar T (2010) Rethinking sustainable development: urban management, engineering, and design. IGI Global

Zamagni A, Amerighi O, Buttol P (2011) Strengths or bias in social LCA? Int J Life Cycle Assess 16:596–598. https://doi.org/10.1007/s11367-011-0309-3

Download references

Author information

Authors and affiliations.

Department of Economy, Engineering, Society and Business Organization, University of “Tuscia, ” Via del Paradiso 47, 01100, Viterbo, VT, Italy

Cecilia Silvestri, Michela Piccarozzi & Alessandro Ruggieri

Department of Engineering, University of Rome “Niccolò Cusano, ” Via Don Carlo Gnocchi, 3, 00166, Rome, Italy

Luca Silvestri

You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Cecilia Silvestri .

Ethics declarations

Competing interests.

The authors declare no competing interests.

Additional information

Communicated by Monia Niero

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

The original online version of this article was revised: a number of ill-placed paragraph headings were removed and the source indication "Authors' elaborations" was added to Tables 1-3.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 31 KB)

Rights and permissions.

Reprints and permissions

About this article

Silvestri, C., Silvestri, L., Piccarozzi, M. et al. Toward a framework for selecting indicators of measuring sustainability and circular economy in the agri-food sector: a systematic literature review. Int J Life Cycle Assess (2022). https://doi.org/10.1007/s11367-022-02032-1

Download citation

Received : 15 June 2021

Accepted : 16 February 2022

Published : 02 March 2022

DOI : https://doi.org/10.1007/s11367-022-02032-1

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Agri-food sector
Sustainability
Circular economy
Triple bottom line
Life cycle assessment
Find a journal
Publish with us
Track your research

Open access
Published: 15 February 2023

Literature review of stroke assessment for upper-extremity physical function via EEG, EMG, kinematic, and kinetic measurements and their reliability

Rene M. Maura ORCID: orcid.org/0000-0001-6023-9038 1 ,
Sebastian Rueda Parra 4 ,
Richard E. Stevens 2 ,
Douglas L. Weeks 3 ,
Eric T. Wolbrecht 1 &
Joel C. Perry 1

Journal of NeuroEngineering and Rehabilitation volume 20 , Article number: 21 ( 2023 ) Cite this article

5987 Accesses

15 Citations

Metrics details

Significant clinician training is required to mitigate the subjective nature and achieve useful reliability between measurement occasions and therapists. Previous research supports that robotic instruments can improve quantitative biomechanical assessments of the upper limb, offering reliable and more sensitive measures. Furthermore, combining kinematic and kinetic measurements with electrophysiological measurements offers new insights to unlock targeted impairment-specific therapy. This review presents common methods for analyzing biomechanical and neuromuscular data by describing their validity and reporting their reliability measures.

This paper reviews literature (2000–2021) on sensor-based measures and metrics for upper-limb biomechanical and electrophysiological (neurological) assessment, which have been shown to correlate with clinical test outcomes for motor assessment. The search terms targeted robotic and passive devices developed for movement therapy. Journal and conference papers on stroke assessment metrics were selected using PRISMA guidelines. Intra-class correlation values of some of the metrics are recorded, along with model, type of agreement, and confidence intervals, when reported.

A total of 60 articles are identified. The sensor-based metrics assess various aspects of movement performance, such as smoothness, spasticity, efficiency, planning, efficacy, accuracy, coordination, range of motion, and strength. Additional metrics assess abnormal activation patterns of cortical activity and interconnections between brain regions and muscle groups; aiming to characterize differences between the population who had a stroke and the healthy population.

Range of motion, mean speed, mean distance, normal path length, spectral arc length, number of peaks, and task time metrics have all demonstrated good to excellent reliability, as well as provide a finer resolution compared to discrete clinical assessment tests. EEG power features for multiple frequency bands of interest, specifically the bands relating to slow and fast frequencies comparing affected and non-affected hemispheres, demonstrate good to excellent reliability for populations at various stages of stroke recovery. Further investigation is needed to evaluate the metrics missing reliability information. In the few studies combining biomechanical measures with neuroelectric signals, the multi-domain approaches demonstrated agreement with clinical assessments and provide further information during the relearning phase. Combining the reliable sensor-based metrics in the clinical assessment process will provide a more objective approach, relying less on therapist expertise. This paper suggests future work on analyzing the reliability of metrics to prevent biasedness and selecting the appropriate analysis.

Stroke is one of the leading causes of death and disability in developed countries. In the United States, a stroke occurs every 40 s, ranking stroke as the fifth leading cause of death and the first leading cause of disability in the country [ 1 ]. The high prevalence of stroke, coupled with increasing stroke survival rates, puts a growing strain on already limited healthcare resources; the cost of therapy is elevated [ 2 ] and restricted mostly to a clinical setting [ 3 ], leading to 50% of survivors that reach the chronic stage experiencing severe motor disability for upper extremities [ 4 ]. This highlights the need for refined (improved) assessment which can help pair person-specific impairment with appropriately targeted therapeutic strategies.

Rehabilitation typically starts with a battery of standardized tests to assess impairment and function. This initial evaluation serves as a baseline of movement capabilities and usually includes assessment of function during activities of daily living (ADL). Because these clinical assessments rely on trained therapists as raters, the scoring scale is designed to be discrete and, in some cases, bounded. While this improves the reliability of the metric [ 5 ] (i.e., raters more likely to agree), it also reduces the sensitivity of the scale. Furthermore, those assessment scales that are bounded, such as the Fugl-Meyer Assessment (FMA) [ 6 ], Ashworth or Modified Ashworth (MA) Scale [ 7 ], and Barthel Index [ 8 ], suffer from floor/ceiling effects where the limits of the scales become insensitive to the extremes of impairment and function. It is therefore important to develop new clinical assessment methods that are objective, quantifiable, reliable, and sensitive to change over the full range of function and impairment.

Over the last several decades, robotic devices have been designed and studied for administering post-stroke movement therapy. These devices have begun being adopted into clinical rehabilitation practice. More recently, researchers have proposed and studied the use of robotic devices to assess stroke-related impairments as an approach to overcome the limitations of existing clinical measures previously discussed [ 9 , 10 , 11 , 12 ]. Robots may be equipped with sensitive measurement devices that can be used to rate the person’s performance in a predefined task. These devices can include measuring kinematic (position/velocity), kinetic (force/torque), and/or neuromuscular (electromyography/electroencephalography) output from the subject during the task. Common sensor-based robotic metrics for post-stroke assessment included speed of response, planning time, movement planning, smoothness, efficiency, range, and efficacy [ 13 , 14 ]. Figure 1 demonstrates an example method for comprehensive assessment of a person who has suffered a stroke with data acquired during robotically administered tests. Furthermore, there is potential for new and more comprehensive knowledge to be gained from a wider array of assessment methods and metrics that combine the benefits of biomechanical (e.g., kinematic and kinetic) and neurological (e.g., electromyographic and electroencephalographic) measures [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ].

Example of instrument for upper extremities bilateral biomechanical and neuromuscular assessment. From this data, a wide variety of measures and metrics for assessment of upper-extremity impairment and function may be reported

Biomechanical assessment

Many classical methods of assessing impairment or function involve manual and/or instrumented quantification of performance through measures of motion (i.e., kinematic) and force (i.e., kinetic) capabilities. These classical methods rely on the training of the therapist to evaluate the capabilities of the person through keen observation (e.g., FMA [ 6 ] and MA [ 7 ]). The quality of kinematic and kinetic measures can be improved with the use of electronic-based measurements [ 23 ]. Robotic devices equipped with electronic sensors have the potential to improve the objectivity, sensitivity, and reliability of the assessment process by providing a means for more quantitative, precise, and accurate information [ 9 , 10 , 11 , 12 , 24 , 25 , 26 , 27 , 28 ]. Usually, the electronic sensors on a rehabilitation robotic device are used for control purposes [ 29 , 30 , 31 ]. Robotics can also measure movement outputs, such as force or joint velocities, which the clinician may not be able to otherwise measure as accurately (or simultaneously) using existing clinical assessment methods [ 23 ]. With accurate and repeatable measurement of forces and joint velocities, sensor-based assessments have the potential to assess the person’s movement in an objective and quantifiable way. This article reviews validity and reliability of biomechanical metrics in relationship to assessment of motor function for upper extremities.

Electrophysiological features for assessment

Neural signals that originate from the body can be measured using non-invasive methods. Among others, electroencephalograms (EEG) measure cortical electrical activity, and electromyograms (EMG) measure muscle electrical activity. The relative low cost, as well as the noninvasive nature of these technologies make them suitable for studying changes in cortical or muscle activation caused by conditions or injuries of the brain, such as the ones elicited by stroke lesions [ 32 ].

Initially, EMG/EEG were used strictly as clinical diagnostic tools [ 33 , 34 ]. Recent improvements in signal acquisition hardware and computational processing methods have increased their use as viable instruments for understanding and treating neuromuscular diseases and neural conditions [ 32 ]. Features extracted from these signals are being researched to assess their relationship to motor and cognitive deficits [ 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ] and delayed ischemia [ 34 , 43 ], as well as to identify different uses of the signals that could aid rehabilitation [ 44 ]. Applications of these features in the context of stroke include: (1) commanding robotic prostheses [ 45 , 46 ], exoskeletons [ 21 , 47 , 48 ], and brain-machine interfaces [ 44 , 49 , 50 , 51 ]; and (2) bedside monitoring for sub-acute patients and thrombolytic therapy [ 52 , 53 , 54 ]. Here we review the validity and reliability of metrics derived from electrophysiological signals in relationship to stroke motor assessment for upper extremity.

Reliability of metrics

Robotic or sensor-based assessment tools have not gained widespread clinical acceptance for stroke assessment. Numerous barriers to their clinical adoption remain, including demonstrating their reliability and providing sufficient validation of robotic metrics with respect to currently accepted assessment techniques [ 55 ]. In the assessment of motor function with sensor-based systems, several literature reviews reveal a wide spectrum of sensor-based metrics to use for stroke rehabilitation and demonstrate their validity [ 13 , 42 , 56 , 57 , 58 , 59 , 63 , 64 ]. However, in addition to demonstrating validity, new clinical assessments must also demonstrate good or excellent reliability in order to support their adoption in the clinical field. This is achieved by: (1) comparing multiple measurements on the same subject (test–retest reliability), and (2) checking agreement between multiple raters of the same subject (inter-rater reliability). Reliability quantifies an assessment’s ability to deliver scores that are free from measurement error [ 65 ]. Previous literature reviews have presented limited, if any, information on the reliability of the biomechanical robotic metrics. Murphy and Häger [ 66 ], Wang et al. [ 56 ], and Shishov et al. [ 67 ] reviewed reliability, but omitted some important aspects of intra-class correlation methods used in the study (e.g., the model type and/or the confidence interval), which are required when analyzing intra-class correlation methods for reliability [ 68 ]. If the reliability is not properly analyzed and reported, the study runs the risk of having a biased result. Murphy and Häger [ 66 ] also found a lack of studies determining the reliability of metrics in 2015. Since electronic-based assessments require the use of a therapist or an operator to administer the test, an inter-observer reliability test should be investigated to observe the effect of the test administrators on the assessment process. Therefore, both test–retest and inter-observer reliability in biomechanical and electrophysiological metrics are reviewed to provide updated information on the current findings of the metrics’ reliability.

Integrated metrics

Over the past 50 years, numerous examples of integrated metrics have provided valuable insight into the inner workings of human arm function. In the 1970s EMG was combined with kinematic data in patients with spasticity to understand muscle patterns during ballistic arm reach movements [ 69 ], the affects of pharmacological intervention on spastic stretch reflexes during passive vs. voluntary movement [ 70 ], and in the 1990s EMG was combined with kinetic data to understand the effects of abnormal synergy patterns on reach workspace when lifting the arm against gravity [ 71 ]. This work dispelled long-standing theories of muscular weakness and spasticity alone being the major contributors to arm impairment. More recently, quantified aspects of processed EEG and EMG signals are being combined with kinematic data to investigate the compensatory role, and relation to shoulder-related abnormal muscle synergies of the contralesional secondary sensorimotor cortex, in a group of chronic stroke survivors [ 72 ]. These and other works demonstrate convincingly the value of combined metrics and the insights they can uncover that isolated metrics cannot discover alone.

To provide further information on the stroke severity and the relearning process during stroke therapy, researchers are investigating a multi-modal approach using biomechanical and neuromuscular features [ 15 , 16 , 18 , 19 , 21 , 22 ]. Combining both neuromuscular and biomechanical metrics will provide a comprehensive assessment of the person’s movement starting from motor planning to the end of motor execution. Neuromuscular output provides valuable information on the feedforward control and the movement planning phase [ 22 ]. However, neuromuscular signals provides little information on the movement quality that is often investigated with movement function tests or biomechanical output [ 21 ]. Also, using neuromuscular data will provide information to therapist on the neurological status and nervous system reorganization of the person that biomechanical information cannot provide [ 73 ]. The additional information can assist in developing more personalized care for the person with stroke, as well as offer considerable information on the changes that occur at the physiological level.

Paper overview

This paper reviews published sensor-based methods, for biomechanical and neuromuscular assessment of impairment and function after neurological damage, and how the metrics resulting from the assessments, both alone and in combination, may be able to provide further information on the recovery process. Specifically, methods and metrics utilizing digitized kinematic, kinetic, EEG, and EMG data were considered. The “Methods” section explains how the literature review was performed. In “Measures and methods based on biomechanical performance” section, prevailing robotic assessment metrics are identified and categorized including smoothness, resistance, efficiency, accuracy, efficacy, planning, range-of-motion, strength, inter-joint coordination, and intra-joint coordination. In “Measures and methods based on neural activity using EEG/EMG” section, EEG- and EMG-derived measures are discussed by the primary category of analysis performed to obtain them, including frequency power and coherence analyses. The relationship of each method and metric to stroke impairment and/or function is also discussed. Section “Reliability of measures” discusses the reliability of sensor-based metrics and some of the complications in demonstrating the effectiveness of the metrics. Section “Integrated metrics” reviews previous studies on combining biomechanical and neuromuscular data to provide further information on the changes occurring during assessment and training. Finally, Section “Discussions and conclusions” concludes the paper with a discussion on the advantages of combining multi-domain data, which of the metrics from the earlier sections should be considered in future robotic applications, as well as the ones that still require more investigation for either validity and/or reliability.

A literature review was performed following PRISMA guidelines [ 74 ] on biomechanical and neuromuscular assessment in upper-limb stroke rehabilitation. The review was composed of two independent searches on (1) biomechanical robotic devices, and (2) electrophysiological digital signal processing. Figures 2 and 3 show the selection process of the electrophysiological and biomechanical papers, respectively. Each of these searches applied the following steps: In step 1, each researcher searched in Google Scholar for papers between 2000 and 2021 (see Table 1 for search terms and prompts). In step 2, resulting titles and abstracts were screened to remove duplicates, articles in other languages, and articles not related to the literature review. In step 3, researchers read the full texts of articles screened in step 2, papers qualifying for inclusion using the Literature Review Criteria in Table 1 were selected. Finally, in step 4, selected articles from independent review process were read by the other researcher. Uncertainties in determining if a paper should be included/excluded were discussed with the whole research group. Twenty-four papers focus on biomechanical measures (kinematic and kinetic), thirty-three focus on electrophysiological measures (EEG/EMG), and six papers on multimodal approaches combining biomechanical and neuromuscular measures to assess stroke. Three of the six multimodal papers are also reported in the biomechanical section and 3 papers were hand-picked. A total of 60 papers are reviewed and reported.

PRISMA flowchart on the selection for electrophysiological papers

PRISMA flow chart for the selection for biomechanical papers

Measures and methods based on biomechanical performance

This review presents common robotic metrics which have been previously used to assess impairment and function after stroke. Twenty-five biomechanical papers are reviewed, which used both sensor-based and traditional clinical metrics to assess upper-extremity impairment and function. The five common metrics included in the reviewed studies measured the number of velocity peaks (~ 9 studies), path-length ratio (~ 8 studies), the max speed of the arm (~ 7 studies), active range of motion (~ 7 studies), and movement time (~ 7 studies). The metrics are often compared to an established clinical assessment to determine validity of the metric. The sensor-based metrics can be categorized by the aspect in which they evaluate movement quality similar to De Los Reyes-Guzmán et al.: smoothness, efficiency, efficacy, accuracy, coordination, or range of motion [ 14 ]. Resistance, Movement Planning, Coordination, and Strength are included as additional categories since some of the reviewed sensor-based metrics best evaluate those movement aspects. Examples of common evaluation activities and specific metrics that have been computed to quantify movement quality are outlined in Table 2 .

Lack of arm movement smoothness is a key indicator of underlying impairment [ 79 ]. Traditional therapist-administered assessments do not computationally measure smoothness leaving therapists unable to determine the degree to which disruption to movement smoothness is compromising motor function and, therefore, ADL. Most metrics that have been developed to quantify smoothness are based on features of the velocity profile of an arm movement, such as speed [ 80 , 81 ], speed arc length [ 79 ], local minima of velocity [ 10 ], velocity peaks [ 75 , 76 , 81 ], tent [ 80 ], spectral [ 25 ], spectral arc length [ 25 , 81 ], modified spectral arc length [ 79 ], and mean arrest period ratio [ 76 ]. Table 3 summarizes the smoothness metrics and their corresponding equations with equation numbers for reference. The speed metric is expressed as a ratio between the mean speed and the peak speed (Eq. 1). The speed arc length is the temporal length of the velocity profile (Eq. 2). Local minima of velocity and the velocity peaks metrics are measured by counting the number of minimum (Eq. 3) or maximum (Eq. 4) peaks in the velocity profile, respectively. The tent metric is a graphical approach that divides the area under the velocity curve by the area of a single peak velocity curve (Eq. 5). The spectral metric is the summation of the maximal Fourier transformed velocity vector (Eq. 6). The spectral arc-length metric is calculated from the frequency spectrum of the velocity profile by performing a fast Fourier transform operation and then computing the length (Eq. 7). The modified spectral arc length adapts the cutoff frequency according to a given threshold velocity and an upper-bound cutoff frequency (Eq. 8). The modified spectral arc length is then independent of temporal movement scaling. The mean arrest period ratio is the time portion that movement speed exceeds a given percentage of peak speed (Eq. 9).

Another commonly used approach is to analyze the jerk (i.e., the derivative of acceleration) profile. The common ways to assess smoothness using the jerk profile are root mean square jerk, mean rectified jerk, normalized jerk, and the logarithm of dimensionless jerk. The root mean square jerk takes the root-mean-square of the jerk that is then normalized by the movement duration [ 82 ] (Eq. 10). The mean rectified jerk (normalized mean absolute jerk) is the mean of the magnitude jerk normalized or divided by the peak velocity [ 80 , 82 ] (Eq. 11). The normalized jerk (dimensionless-squared jerk) is the square of the jerk times the duration of the movement to the fifth power over the length squared (Eq. 12). It is then integrated over the duration and square rooted. The normalized jerk can be normalized by mean speed, max speed, or mean jerk [ 80 ]. The logarithm of dimensionless jerk (Eq. 13) is the logarithm of normalized jerk defined in Eq. 12 [ 81 ].

It has yet to be determined which smoothness metric is more effective for characterizing recovery of smooth movement. According to Rohrer et al. [ 80 ], the metrics of speed, local minima of velocity, peaks, tent, and mean arrest period ratio showed increases in smoothness for inpatient recovery from stroke, but the mean rectified jerk metric seemed to show a decrease in smoothness as survivors of stroke recovered. Rohrer et al. warned that a low smoothness factor in jerk does not always mean the person is highly impaired. The spectral arc-length metric showed a consistent increase in smoothness as the number of sub-movements decreased [ 25 ], whereas the other metrics showed sudden changes in smoothness. For example, the mean arrest period ratio and the speed metric showed an increase in smoothness with two or more sub-movements, but when two sub-movements started to merge, the smoothness decreased. As a result, the spectral arc-length metric appears to capture change over a wider range of movement conditions in recovery in comparison to other metrics.

The presence of a velocity-dependent hyperactive stretch reflex is referred to as spasticity [ 83 ]. Spasticity results in a lack of smoothness during both passive and active movements and is more pronounced with activities that involve simultaneous shoulder abduction loading and extension of the elbow, wrist, or fingers [ 83 ], which are unfortunately quite common in ADL. A standard approach to assessing spasticity by a therapist involves moving a subject’s passive arm at different velocities and checking for the level of resistance. While this manual approach is subjective, electronic sensors have the potential to assess severity of spasticity in much more objective ways. Centen et al. report a method to assess the spasticity of the elbow using an upper-limb exoskeleton [ 84 ] involving the measurement of peak velocity, final angle, and creep. Sin et al., similarly performed a comparison study between a therapist moving the arm versus a robot moving the arm. An EMG sensor was used to detect the catch and compared with a torque sensor to detect catch angle for the robotic motion [ 85 ]. The robot moving the arm seemed to perform better with the inclusion of either an EMG or a torque sensor than with the therapist moving the arm and the robot simply recording the movement. A related measure that may be correlated with spasticity is the assessment of joint resistance torques during passive movement [ 76 ]. This can provide an assessment of the velocity-dependent resistance to movement that arises following stroke.

Efficiency measures movement fluency in terms of both task completion times and spatial trajectories. In point-to-point reaching, people who have suffered a stroke commonly display inefficient paths in comparison to their healthy side or compared to subjects who are unimpaired [ 10 ]. During the early phases of recovery after stroke, subjects may show slow overall movement speed resulting in longer task times. As recovery progresses, overall speed tends to increase and task times decrease, indicating more effective and efficient motor planning and path execution. Therapists usually observe the person’s efficiency in completing a task and then rate the person’s ability in completing a task in a timely manner. Therefore, both task time (or movement time) [ 10 , 76 , 77 , 86 , 87 ] and mean speed [ 25 , 75 , 77 , 81 , 86 ] are effective ways to assess temporal efficiency. Similar measures used by Wagner et al. include peak-hand velocity and time to peak-hand velocity [ 87 ]. To measure spatial efficiency of movement, both Colombo et al. [ 75 ], Mostafavi [ 77 ], and Germanotta [ 86 ] calculated the movement path length and divided it by the straight-line distance between the start and end points. This is known as the path-length ratio.

Movement planning

Movement planning is associated with feedforward sensorimotor control, elements that occur before the initial phase of movement. A common approach is to use reaction time to assess the duration of the planning phase. In a typical clinical assessment, a therapist can only observe/quantify whether movement can be initiated or not, but has no way to quantify the lag between the signal to initiate movement and initiation of movement. Keller et al., Frisoli et al., and Mostafavi et al. quantified the reaction time to assess movement planning [ 10 , 76 , 77 ] in subjects who have suffered a stroke. Mostafavi assessed movement planning in three additional ways by assessing characteristics of the actual movement: change in direction, movement distance ratio, and maximum speed ratio [ 77 ]. The change in direction is the angular deviation between the initial movement vector and the straight line between the start and end points. The first-movement-distance ratio is the ratio between the distance the hand traveled during the initial movement and the total distance between start and end points. The first-movement-maximum speed ratio is the ratio of the maximum hand speed during the initial phase of the movement divided by the global hand speed for the entire movement task.

Movement efficacy

Movement efficacy measures the person’s ability to achieve the desired task without assistance. While therapists can assess the number of completed repetitions, they have no means to kinetically quantify amount of assistance required to perform a given task. Movement efficacy is quantified by robot sensor systems that can measure: (a) person-generated movement, and/or (b) the amount of work performed by the robot to complete the movement (e.g., when voluntary person-generated movement fails to achieve a target). Hence, movement efficacy can involve both kinematic and kinetic measures. A kinematic metric that can be used to represent movement efficacy is the active movement index, which is calculated by dividing the portion of the distance the person is to complete by the total target distance for the task [ 75 ]. An example metric based on kinetic data is the amount of assistance metric, proposed by Balasubramanian et al. [ 25 ]. It is calculated by estimating the work performed by the robot to assist voluntary movement, and then dividing it by the work performed by the robot as if the person performs the task without assistance from the robot. A similar metric obtained by Germanotta et al. calculates the total work by using the movement’s path length, but Germanotta et al. also calculate the work generated towards the target [ 86 ].

Movement accuracy

Movement accuracy has been characterized by the error in the end-effector trajectory compared to a theoretical trajectory. It measures the person’s ability to follow a prescribed path, whereas movement efficiency assesses the person’s ability to find the most ideal path to reach a target. Colombo et al. measured movement accuracy in people after stroke by calculating the mean-absolute value of the distance, which is the mean absolute value of the distance between each point on the person’s path and the theoretical path [ 75 ]. Figure 4 demonstrates the difference between path-length ratio and mean-absolute value of the distance. The mean-absolute value of the distance computes the error between a desired trajectory and the actual, and the path-length ratio computes the total path length the person’s limb has traveled. Another similar metric is the average inter-quartile range, which quantifies the average “spread” among several trajectories [ 15 ]. Balasubramanian et al. characterized movement accuracy as a measure of the subject’s ability to achieve a target during active reaching. They refer to the metric as movement synergy [ 25 ], and calculate it by finding the distance between the end-effector’s final location and the target location.

Difference between path-length ratio and mean absolute value of the distance. A Path-length ratio. $d_{ref}$ is the theoretical distance the hand should travel between the start and end point. $d_{total}$ is the total distance the hand travelled from Start to End. B Mean absolute value of the distance. $d_{i}$ is the distance between the theoretical path and the actual hand path

Intra-limb coordination

Intra-limb (inter-joint) coordination is a measure of the level of coordination achieved by individual joints of a limb or between multiple joints of the same limb (i.e., joint synergy) when performing a task. Since the upper limb consists of kinematic redundancies, the human arm can achieve a desired outcome in multiple ways. For example, a person might choose to move an atypical joint in order to compensate for a loss of mobility in another joint. Frisoli et al. and Bosecker et al. used the shoulder and elbow angle to find a linear correlation between the two angles in a movement task that required multi-joint movement [ 10 , 78 ]. In terms of clinical assessment, joint angle correlations can illustrate typical or atypical contribution of a joint while performing a multi-joint task.

Inter-limb coordination

Inter-limb coordination refers to a person’s ability to appropriately perform bilateral movements with affected and unaffected arms. Therapists observe the affected limb by often comparing to the unaffected limb during a matching task, such as position matching. Matching can either be accomplished with both limbs moving simultaneously or sequentially, and typically without the use of vision. Dukelow et al. used position matching to obtain measures of inter-limb coordination [ 24 ], including trial-to-trial variability, spatial contraction/expansion, and systematic shifts. Trial-to-trial variability is the standard deviation of the matching hand’s position for each location in the x (distal/proximal), y (anterior/posterior), and both in x and y in the transverse plane. Spatial contraction/expansion is the ratio of the 2D work area of the target hand to the 2D work area of the matching hand during a matching task. Systematic shifts were found by calculating the mean absolute position error between the target and matching hand for each target location.

Semrau et al. analyzed the performance of subjects in their ability to match their unaffected arm with the location of their affected arm [ 88 ]. In the experiment, a robot moved the affected arm to a position and the person then mirrored the position with the unaffected side. The researchers compared the data when the person was able to see the driven limb versus when they were unable to see the driven limb. The initial direction error, path length ratio, response latency, peak speed ratio, and their variabilities were calculated to assess the performance of the person’s ability to perform the task.

Range of motion

Range of motion is a measure of the extent of mobility in one or multiple joints. Traditionally, range of motion can be measured with the use of a goniometer [ 89 ]. The goniometer measures the individual joint range of motion, which takes considerable time. Range of motion can be expressed as a 1-DOF angular measure [ 76 , 89 ], a 2-DOF planar measure (i.e., work area) [ 82 ], or a 3-DOF spatial measure (i.e., workspace) [ 77 ]. Individual joints are commonly measured in joint space, whereas measures of area or volume are typically given in Cartesian space. In performing an assessment of work area or workspace with a robotic device, the measure can be estimated either by: (a) measuring individual joint angles with an exoskeleton device and then using these angles to compute the region swept out by the hand, or (b) directly measuring the hand or fingertips with a Cartesian (end-effector) device. The measurement of individual joint range of motion (ROM) as well as overall workspace have significant clinical importance in assessing both passive (pROM) and active (aROM) range of motion. To measure pROM, the robot drives arm movement while the person remains passive. The pROM is the maximum range of motion the person has with minimal or no pain. For aROM, a robot may place the arm in an initial position/orientation from which the person performs unassisted joint movements to determine the ROM of particular joints [ 76 ], or the area or volume swept by multiple joints. Lin et al. quantified the work area of the elbow and shoulder using potentiometers and derived test–retest reliability [ 89 ]. The potentiometer measurements were then compared to therapist measurements to determine validity.

Measures of strength evaluate a person’s ability to generate a force in a direction or a torque about a joint. Strength measurements may involve single or multiple joints. At the individual joint level, strength is typically measured from a predefined position of a person’s arm and/or hand. The person then applies a contraction to produce a torque at the assessed joint [ 76 , 78 ]. Multi-joint strength may also be measured by assessing strength and/or torque in various directions at distal locations along the arm, such as the hand. Lin et al. compared the grip strength obtained from load cells to a clinical method using precise weights, which showed excellent concurrent validity [ 89 ].

Measures and methods based on neural activity using EEG/EMG

Although much information can be captured and analyzed using the kinematic and kinetic measures listed above, their purview is limited. These measures provide insight into the functional outcomes of neurological system performance but provide limited perspective on potential contributing sources of measured impairment [ 90 ]. For a deeper look into the neuromuscular system, measures based on neurological activation are often pursued. As a complement to biomechanical measures, methods based on quantization of neural activity like EEG and EMG have been used to characterize the impact of stroke and its underlying mechanisms of impairments [ 91 , 92 ]. Over the past 20 years, numerous academic research studies have used these measures to explore the effects of stroke, therapeutic interventions, or time on the evolution of abnormal neural activity [ 91 ]. Groups with different levels of neurological health are commonly compared (e.g., chronic/acute/subacute stroke vs. non-impaired, or impairment level) or other specific experimental characteristics (e.g., different rehabilitation paradigms [ 93 , 94 ]). With this evidence, the validity of these metrics has been tested; however, the study of reliability of these metrics is needed to complete the jump from academic to clinical settings.

Extracting biomarkers from non-invasive neural activity requires careful decomposition and processing of raw EEG and EMG recordings [ 32 ]. Various methods have been used, and the results have produced a growing body of evidence for the validity of these biomarkers in providing insight on the current and future state of motor, cognitive, and language skills in people after stroke [ 38 , 95 ]. Some of the biomarkers derived from EEG signals include: power-related band-specific information [ 34 , 35 , 43 , 47 , 53 , 54 , 96 , 97 , 98 , 99 , 100 , 101 ], band frequency event-related synchronization and desynchronization (ERS/ERD) [ 22 , 51 , 102 , 103 ], intra-cortical coherence or functional connectivity [ 39 , 59 , 73 , 94 , 104 , 105 , 106 , 107 , 108 , 109 ], corticomuscular coherence (CMC) [ 37 , 110 , 111 , 112 , 113 ], among others [ 114 , 115 ]. Biomarkers extracted from EEG can be used to assess residual functional ability [ 38 , 54 , 73 , 97 , 98 , 99 ], derive prognostic indicators [ 34 , 43 , 104 ], or categorize people into groups (e.g., to better match impairments with therapeutic strategies) [ 39 , 47 , 58 , 116 ].

In the following subsections, valid biomarkers derived mostly from EEG signal features (relationship with motor outcome for a person after stroke) will be discussed and introduced theoretically. Distinctions will be made about the stage after stroke when signals were taken. Findings are reported from 33 studies that have examined the relationship between extracted neural features and motor function for different groups of people after stroke. These records are grouped by quantization methods used including approaches based on measures of frequency spectrum power (n = 9), inter-regional coherence (n = 10 for cortical coherence and n = 9 for CMC), and reliability (n = 5).

Frequency spectrum power

Power measures the amount of activity within a signal that occurs at a specific frequency or range of frequencies. Power can be computed in absolute or relative terms (i.e., with respect to other signals). It is often displayed as a power density spectrum where the magnitudes of signal power can be seen across a range of frequencies. In electro-cognitive research, the representation of power within specific frequency bands has been useful to explain brain activity and to characterize abnormal oscillatory activity due to regional neurological damage [ 32 , 117 ].

Frequency bands in EEG content

Electrical activity in the brain is dominated primarily by frequencies from 0–100 Hz where different frequency bands correspond with different states of activity: Delta (0–4 Hz) is associated with deep sleep, Theta (4–8 Hz) with drowsiness, Alpha (8–13 Hz) with relaxed alertness and important motor activity [ 117 ], and Beta (13–31 Hz) with focused alertness. Gamma waves (> 32 Hz) are also seen in EEG activity; however, their specific relationship to level of alertness or consciousness is still debated [ 32 , 117 ]. Important cognitive tasks have been found to trigger activity in these bands in different ways. Levels of both Alpha and Delta activity have also been shown to be affected by stroke and can therefore be examined as indicators of prognosis or impairment in sub-acute and chronic stroke [ 52 , 100 , 118 ].

Power in acute and sub-acute stroke

For individuals in the early post-stroke (i.e., sub-acute) phase, abnormal power levels can be an indicator of neurological damage [ 98 ]. Attenuation of activity in Alpha and Beta bands have been observed in the first hours after stroke [ 100 ] preceding the appearance of abnormally high Delta activity. Tolonen et al. reported a high correlation between Delta power and regional Cerebral Blood Flow (rCBF). This relationship appears during the sub-acute stroke phase and has been used to predict clinical, cognitive, and functional outcomes [ 119 ]. Delta activity has also been shown to positively correlate with 1-month National Institutes of Health Stroke Scale (NIHSS) [ 52 ] and 3-month Rankin scale [ 36 ] assessments.

Based on these findings, several QEEG (Quantitative Electroencephalography) metrics involving ratios of abnormal slow (Delta) and abnormal fast (Alpha and Beta) activity have been developed. The Delta-Alpha Ratio (DAR), Delta-Theta Ratio (DTR), and (Delta + Theta)/(Alpha + Beta) Ratio (DTABR also known as PRI for Power Ratio Index) relate amount of abnormal slow activity with the activity from faster bands and have been shown to provide valuable insight into prognosis of stroke outcome and thrombolytic therapy monitoring [ 98 ]. Increased DAR and DTABR have been repeatedly found to be the QEEG indices that best predict worse outcome for the following: comparing with the Functional Independence Measure and Functional Assessment Measure (FIM-FAM) at 105 days [ 53 ], Montreal Cognitive Assessment (MoCa) at 90 days [ 54 ], NIHSS at 1 month [ 35 ], modified ranking scale (mRS) at 6 months [ 105 ], NIHSS evolution at multiple times [ 120 ], and NIHSS at 12 months [ 96 ]. DAR was also used to classify people in the acute phase and healthy subjects with an accuracy of 100% [ 58 ].

The ability of basic EEG monitoring to derive useful metrics during the early stage of stroke has made EEG collection desirable for people who have suffered a stroke in intensive care settings. The derived QEEG indices have proven to be helpful to determine Delayed Cerebral Ischemia (DCI), increased DAR [ 43 ], and increased Delta power [ 34 , 118 ]. However, finding the electrode montage with the least number of electrodes that still reveals the necessary information for prognoses is one of the biggest challenges for this particular use of EEG. Comparing DAR from 19 electrodes on the scalp with 4 electrodes on the frontal cortex suggests that DAR from 4 frontal electrodes may be enough to detect early cognitive and functional deficits [ 53 ]. Studies explored the possibility of a single-electrode montage over the Fronto-Parietal area (FP1); the DAR and DTR from this electrode might be a valid predictor of cognitive function after stroke when correlated with the MoCA [ 54 ], relative power in Theta band correlated with mRS and modified Barthel Index (mBI) 30 and 90 days after stroke [ 121 ].

Power in chronic stroke

The role of power-related QEEG indices during chronic stroke and progression of motor functional performance have been examined with respect to rehabilitation therapies, since participants have recovered their motion to a certain degree [ 4 ]. Studies have shown that therapy and functional activity improvements correlate with changes of the shape and delay of event-related desynchronization and synchronization (ERD-ERS) for time–frequency power features when analyzing Alpha and Beta bands on the primary motor cortex for ipsilesional and contralesional hemispheres [ 21 , 22 , 122 ]. Therapies with better outcome tend to have reduced Delta rhythms and increased Alpha rhythms [ 122 ].

Bertolucci [ 47 ] compared starting power spectrum density in different bands for both hemispheres with changes in WMFT and FMA over time. Increased global Alpha and Beta activity was shown to correlate with better WMFT evolution while, increase in contralesional Beta activity was shown to be correlated with FMA evolution. Metrics combining slow and fast activity have also been tested in the chronic stage of stroke, significant negative correlation between DTABR (PRI) at the start of therapy was related to FMA change during robotic therapy [ 99 ]. This finding suggests that DTABR may have promise as prognostic indicators for all stages of stroke.

Brain Symmetry Index (BSI) is a generalized measure of “left to right” (affected to non-affected) power symmetry of mean spectral power per hemisphere. These inter-hemispheric relationships of power have been used as prognostic measures during all stages of stroke. Baseline BSI (during the sub-acute stage) was found to correlate with the FMA at 2 months [ 73 ], mRS at 6 months [ 123 ], and FM-UE predictor when using only theta band BSI for patients in the chronic stage [ 124 ]. BSI can be modified to account for the direction of asymmetry, the directed BSI at Delta and Theta bands proved meaningful to describe evolution from acute to chronic stages of upper limb impairment as measured by FM-UE [ 120 , 125 ]. Table 4 and Table 11 in Appendix 1 communicate power-derived metrics across different stages of stroke documented in this section and their main reported relationships with motor function. Findings are often reported in terms of correlation with clinical tests of motor function.

Brain connectivity (cortical coherence)

Brain connectivity is a measure of interaction and synchronization between distributed networks of the brain and allows for a clearer understanding of brain function. Although cortical damage from ischemic stroke is focal, cortical coherence can explain abnormalities in functionality of remote zones that share functional connections to the stroke-affected zone [ 59 ].

Several estimators of connectivity have been proposed in the literature. Coherency, partial coherence (pCoh) [ 125 ], multiple coherence (mCoh), imaginary part of coherence (iCoh) [ 126 ], Phase Lagged Index (PLI), weighted Phase Lagged Index (wPLI) [ 127 ], and simple ratios of power at certain frequency bands [ 73 ] describe synchronic symmetric activity between ROIs and are referred to as non-directed or functional connectivity [ 128 ]. Estimators based on Granger’s prediction such as partial directed coherence (PDC) [ 129 , 130 , 131 ], or directed transfer Function (DTF) [ 132 , 133 ] and any of their normalizations describe causal relationships between variables and are referred to as directed or effective connectivity [ 134 ]. Connectivity also allows the analysis of brain activity as network topologies, borrowing methods from graph theory [ 32 , 134 ]. Network features such as complexity, linearity, efficiency, clustering, path length, node hubs, and more can be derived from graphs [ 128 ]. Comparisons of these network features among groups with impairment and healthy controls have proven to be interesting tools to understand and characterize motor and functional deficits after stroke [ 108 ].

Studies have used intra- and inter-cortical coherence to expand the clinical understanding of the neural reorganization process [ 59 , 106 , 107 , 108 , 109 ], as a clinical motor and cognitive predictor [ 38 , 94 , 104 , 135 , 136 ], and as a tool to predict the efficacy of rehabilitation therapy [ 94 ]. Table 5 and Table 12 in Appendix 2 briefly summarize the main metrics discussed in this section and their results that are related with motor function assessment. In general, studies have shown that motor deficits in stroke survivors are related to less connectivity to main sensory motor areas [ 38 , 94 , 104 , 137 ], weak interhemispheric sensorimotor connectivity [ 109 , 138 ], less efficient networks [ 106 , 135 ], with less “small world” network patterns [ 108 , 134 ] (small-world networks are optimized to integrate specialized processes in the whole network and are known as an important feature of healthy brain networks).

Survivors of stroke tend to exhibit more modular (i.e., more clustered, less integrated) and less efficient networks than non-impaired controls with the biggest difference occurring in the Beta and Gamma bands [ 106 ]. Modular networks are less “small-world” [ 134 ]; small-world networks are optimized to integrate specialized processes in the whole network and are known as an important feature of healthy brain networks. Such a transition to a less small-world network was observed during the acute stage of stroke (first hours after stroke) and documented to be bilaterally decreased in the Delta band and bilaterally increased in the high Alpha band (also known as Alpha2: 10.5–13 Hz) [ 108 ].

Global connectivity with the ipsilesional primary motor cortex (M1) is the most researched biomarker derived from connectivity and has been studied in longitudinal experiments as a plasticity indicator leading to future outcome improvement [ 38 ], motor and therapy gains [ 94 ], upper limb gains during the sub-acute stage [ 137 ], and as a feature that characterizes stroke survivors’ cognitive deficits [ 104 ]. Pietro [ 38 ] used iCoh to test the weighted node degree (WND), a measure that quantifies the importance of a ROI in the brain, for M1 and reported that Beta-band features are linearly related with motor improvement as measured by FM-UE and Nine-Hole-Peg Test. Beta-band connectivity to ipsilesional M1, as measured by spectral coherence, can be used as a therapy outcome predictor, and more than that, results point heavily toward connectivity between M1 and ipsilesional frontal premotor area (PM) to be the most important variable as a therapy gain predictor; predictions can be further improved by using lesion-related information such as CST or MRI to yield more accurate results [ 94 ]. Comparisons between groups of people with impairment and controls showed significant differences on Alpha connectivity involving ipsilesional M1, this value showed a relation with FMA 3 months for the group with impairment due to stroke [ 104 ].

The relationship between interhemispheric ROI connectivity and motor impairment has been studied. The normalized interhemispheric strength (nIHS) from PDC was used to quantify the coupling between structures in the brain, Beta- and lower Gamma-band features of this quantity in sensorimotor areas exhibited linear relationships with the degree of motor impairment measured by CST [ 136 ]. A similar measure, also derived from PDC used to measure ROI interhemispheric importance named EEG-PDC was used in [ 109 ]; here the results show that Mu-band (10–12 Hz) and Beta-band features could be used to explain results for hand motor function from FM-UE. In another study, Beta debiased weighted phase lag index (dwPLI), correlated with outcome measured by Action Research Arm Test (ARAT) and FM-UE [ 138 ].

Global and local network efficiency for Beta and Gamma bands seem to be significantly decreased in the population who suffered from a stroke compared to healthy controls as reported in [ 106 ]. Newer results, such as the ones pointed out by [ 135 ] found statistically significant relationships between Beta network efficiency, network intradensity derived using a non-parametric method (named Generalized Measure of Association), and functional recovery results given by FM-UE. Global maximal coherence features in the Alpha band have been recently recognized as FM-UE predictors, where coherence was computed using PLI and related to motor outcome by means of linear regression [ 139 ].

Corticomuscular coherence

Corticomuscular coherence (CMC) is a measure of the amount of synchronous activity between signals in the brain (i.e., EEG or MEG) and associated musculature (i.e., EMG) of the body [ 92 ]. Typically measured during voluntary contractions [ 110 ], the presence of coherence demonstrates a direct relationship between cortical rhythms in the efferent motor commands and the discharge of neurons in the motor cortex [ 140 ]. CMC is computed as correlation between EEG and EMG signals at a given frequency. Early CMC research found synchronous (correlated) activity in Beta and low Gamma bands [ 40 , 41 , 42 ]. CMC is strongest in the contralateral motor cortex [ 141 ]. This metric seems to be affected by stroke-related lesions, and thus provides an interesting tool to assess motor recovery [ 111 , 142 , 143 , 144 ]. The level of CMC is lower in the chronic stage of stroke than in healthy subjects [ 112 , 145 ], with chronic stroke survivors showing lower peak CMC frequency [ 146 ], and topographical patterns that are more widespread than in healthy people; highlighting a connection to muscle synergies [ 142 , 147 , 148 ]. CMC has been shown to increase with training [ 37 , 112 , 144 ].

Corticomuscular coherence has been proposed as a tool to: (a) identify the functional contribution of reorganized cortical areas to motor recovery [ 37 , 112 , 141 , 144 , 146 ]; (b) understand functional remapping [ 93 , 142 , 145 ]; and (c) study the mechanisms underlying synergies [ 147 , 148 ]. CMC has shown increased abnormal correlation with deltoid EMG during elbow flexion for people who have motor impairment [ 147 ], and the best muscles to target with rehabilitative interventions [ 148 ]. Changes in CMC have been shown to correlate with motor improvement for different stages of stroke, although follow-up scores based on CMC have not shown statistically significant correlations when compared to clinical metrics [ 37 , 93 ]. Results summarizing CMC on stroke can be found in Table 6 and Table 13 in Appendix 3.

Reliability of measures

Each of the aforementioned measures have the potential to be integrated into robotic devices for upper-limb assessment. However, to improve the clinical acceptability of robotic-assisted assessment, the measurements and derived metrics must meet reliability standards in a clinical setting [ 55 ]. Reliability can be defined as the degree of consistency between measurements or the degree to which a measurement is free of error. A common method to represent the relative reliability of a measurement process is the intraclass correlation coefficient (ICC) [ 150 ]. Koo and Li suggest a guideline on reporting ICC values for reliability that includes the ICC value, analysis model (one-way random effects, two-way random effects, two-way fixed effects, or two-way mixed effects), the model type per Shrout and Fleiss (individual trials or mean of k trials), model definition (absolute agreement or consistency), and confidence interval [ 68 ]. Koo and Li also provide a flowchart in selecting the appropriate ICC based on the type of reliability and rater information. An ICC value below 0.5 indicates poor reliability, 0.5 to 0.75 moderate reliability, 0.75 to 0.9 good reliability, and above 0.9 excellent reliability. The reviewed papers will be evaluated based on these guidelines. For reporting the ICC, the Shrout and Fleiss convention is used [ 68 ]. The chosen reliability studies are included in the tables if the chosen ICC model, type, definition, and confidence interval are identifiable, and the metrics have previously been used in electronic-based metrics. For studies that report multiple ICC scores due to assessment of test–retest reliability for multiple raters, the lowest ICC reported is included to avoid bias in the reported results.

In the assessment of reliability of data from robotic sensors, common ways to assess reliability are to correlate multiple measurements in a single session (intra-session) and correlate multiple measurements between different sessions (inter-session) measurements (i.e., test–retest reliability) [ 151 ]. Checking for test–retest reliability determines the repeatability of the robotic metric. The repeatability is the ability to reproduce the same measurements under the same conditions. Table 7 shows the test–retest reliability of several robotic metrics. For metrics checking for test–retest reliability, a two-way mixed-effects model with either single or multiple measurements may be used [ 68 ]. Since the same set of sensors will be used to assess subjects, the two-way mixed model is used. The test–retest reliability should be checking for absolute agreement. Checking for absolute agreement (y = x) rather than consistency (y = x + b) determines the reliability without a bias or systematic error. For example, in Fig. 5 , for a two-way random effect with a single measurement checking for agreement gives a score of 0.18. When checking for consistency, the ICC score reaches to 1.00. In other words, the bias has no effect on the ICC score when checking for consistency. Therefore, when performing test–retest reliability, it is important to check for absolute agreement to prevent bias in the test–retest result.

Checking agreement versus consistency among ratings. For y = x, the absolute ICC score is 1 and the consistency ICC score is 1.00. For y = x + 1, the agreement ICC score is 0.18 and the consistency ICC score is 1.00. For y = 3x, the absolute ICC score is 0.32 and the consistency ICC score is 0.60. For y = 3x + 1, the absolute ICC score is 0.13 and the consistency ICC score is 0.60

Not only should a robotic metric demonstrate repeatability, it should also be reproducible when different operators are using the same device. Reproducibility evaluates the change in measurements when conditions have changed. Inter-rater reliability tests have been performed to determine the effect raters have when collecting measurements when two or more raters perform the same experimental protocol [ 68 ]. To prevent a biased result, raters should have no knowledge of the evaluations given by other raters, ensuring that raters’ measurements are independent from one another. Table 8 shows the reproducibility of several robotic biomechanical metrics. All the included studies have used two raters to check for reproducibility. The researchers performed a two-way random effects analysis with either a single measurement or multiple measurements to check for agreement.

Measurement reliability of robotic biomechanical assessment

Of the 24 papers reviewed for biomechanical metrics, 13 papers reported on reliability. 6 papers reported reproducibility and 9 papers reported on repeatability. Overall, the metrics seem to demonstrate good to moderate reliability for both repeatability and reproducibility. However, caution should be exercised in determining which robotic metric is more effective in assessing movement quality based on reliability studies. The quality of measurements is highly dependent on the quality of the robotic device and sensors [ 85 ]. Having a completely transparent robot with a sensitive and accurate sensor will further improve assessment of reliability. Also, the researchers have used different versions of the ICC, as seen in Tables 7 and 8 , which complicates direct comparisons of the metrics.

Reliability of electrophysiological signal features

Of the 33 papers reviewed for electrophysiological metrics, 5 papers reported on reliability. 6 papers reported on repeatability. Convenience of acquiring electrophysiological signals non-invasively is relatively new. Metrics for assessment of upper limb motor impairment in stroke, derived from these signals have shown to be valid in academic settings, but most of these valid metrics have yet to be tested for intra- and inter-session reliability to be used in clinical and rehabilitation settings. Few studies found as a result of our systematic search have looked at test–retest reliability of these metrics. Therefore, we found and manually added records reporting on intra- and inter-session reliability on metrics based on electrophysiological features described in section “Measures and methods based on neural activity using EEG/EMG”, even if reliability was not assessed on people with stroke. Relevant results are illustrated in Table 9 .

Spectral power features of EEG signals have been tested during rest [ 153 , 154 ] and task (cognitive and motor) conditions for different cohorts of subjects [ 102 , 103 ]. Some of the spectral features observed during these experiments are related to timed behavior of oscillatory activity due to cued experiments, such as event-related desynchronization of the Beta band (ERD and Beta rebound) [ 102 ] and topographical patterns of Alpha activity R = 0.9302, p < 0.001 [ 103 ].

Test–retest reliability for rest EEG functional connectivity has been explored for few of the estimators listed in section “Measures and methods based on neural activity using EEG/EMG”: (1) for a cohort of people with Alzheimer by means of the amplitude envelope correlation (AEC), phase lag index (PLI) and weighted phase lag index (wPLI) [ 155 ]; (2) in healthy subjects using iCoh and PLI [ 156 ]; and (3) in infants, by studying differences of inter-session PLI graph metrics such as path length, cluster coefficient, and network “small-worldness” [ 60 ]. Reliability for upper limb CMC has not yet been documented (at least to our knowledge). However, an experiment involving testing reliability of CMC for gait reports low CMC reliability in groups with different ages [ 61 ].

EEG and EMG measurements could be combined with kinematic and kinetic measurements to provide additional information about the severity of impairment and decrease the number of false positives from individual measurements [ 21 ]. This could further be used to explain abnormal relationships between brain activation, muscle activation and movement kinematics, as well as provide insight about subject motor performance during therapy [ 15 ]. The availability of EEG and EMG measures can also enhance aspects of biofeedback given during tests or be used to complement other assessments to provide a more holistic picture of an individual’s neurological function.

It has been shown that combining EEG, EMG, and kinematic data using a multi-domain approach can produce correlations to traditional clinical assessments, a summary of some of the reviewed studies is presented in Table 10 . Belfatto et al. have assessed people’s ROM for shoulder and elbow flexion, task time, and computed jerk to measure people’s smoothness, while the EMG was used to measure muscle synergies, and EEG detected ERD and a lateralization coefficient [ 21 ]. Comani et al. used task time, path length, normalized jerk, and speed to measure motor performance while observing ERD and ERS during motor training [ 22 ]. Pierella et al. gathered kinematic data from an upper-limb exoskeleton, which assessed the mean tangential velocity, path-length ratio, the number of speed peaks, spectral arc length, the amount of assistance, task time, and percentage of workspace, while observing EEG and EMG activity [ 18 ]. Mazzoleni et al. used the InMotion2 robot system to capture the movement accuracy, movement efficiency, mean speed, and the number of velocity peaks, while measuring brain activity with EEG [ 16 ]. However, further research is necessary to determine the effectiveness of the chosen metrics and methods compared to other more promising methods to assess function. Furthermore, greater consensus in literature is needed to support the clinical use of more reliable metrics. For example, newer algorithms to estimate smoothness such as spectral arc length have been shown to provide greater validity and reliability than the commonly used normalized jerk metric. Despite this evidence, normalized jerk remains a widely accepted measure of movement smoothness.

Discussions and conclusions

In this paper we reviewed studies that used different sensor-acquired biomechanical and electrophysiological signals to derive metrics related to neuromuscular impairment for stroke survivors; such metrics are of interest for robotic therapy and assessment applications. To assess the ability of a given measure to relate with impairment or motor outcome, we looked for metrics where results have been demonstrated to correlate or predict scores from established clinical assessment metrics for impairment and function (validity). Knowing that a metric has some relationship with impairment and function (i.e., that it is valid) is not enough for it to be used in clinical settings if those results are not repeatable (reliable). Thus, we also reviewed the reliability of metrics and related signal features looking for metrics which produce similar results for the same subject during different test sessions and for different raters. With this information, researchers can aim to use metrics that not only seem to be related with stroke, but also can be trusted, with less bias, and with a simpler interpretation. The main conclusions of this review paper are presented as answers to the following research questions.

Which biomechanical-based metrics show promise for valid assessment of function and impairment?

Metrics derived from kinematic (e.g., position & velocity) and kinetic (e.g., force & torque) sensors affixed to robotic and passive mechanical devices have successfully been used to measure biomechanical aspects of upper-extremity function and impairment in people after stroke. The five common metrics included in the reviewed studies measured the number of velocity peaks (~ 9 studies), path-length ratio (~ 8 studies), the maximum speed of the arm (~ 7 studies), active range of motion (~ 7 studies), and movement time (~ 7 studies). The metrics are often compared to an established clinical assessment to determine validity of the metric. According to the review study by Murphy and Häger, the Fugl-Meyer Assessment for Upper Extremity had significant correlation with movement time, movement smoothness, peak velocity, elbow extension, and shoulder flexion [ 66 ]. The movement time and smoothness showed strong correlation with the Action Research Arm Test, whereas speed, path-length ratio, and end-point error showed moderate correlation. Tran et al. reviewed specifically validation of robotic metrics with clinical assessments [ 57 ]. The review found mean speed, number of peak velocities, movement accuracy, and movement duration to be most promising metrics based on validation with clinical assessments. However, the review mentioned that some studies seem to conflict on the correlation between the robotic metric and clinical measures, which could be due to assessment task, subject characteristics, type of intervention, and robotic device. For further information about the validation of sensor-based metrics, please refer to the previously mentioned literature reviews [ 57 , 66 ].

Which biomechanical-based metrics show promise for repeatable assessment?

Repeatable measures, in which measurement taken by a single instrument and/or person produce low variation within a single task, are a critical requirement for assessment of impairment and function. The biomechanical based metrics that show the most promise for repeatability are range of motion, mean speed, mean distance, normal path length, spectral arc length, number of peaks, and task time. Two or more studies used these metrics and demonstrated good and excellent reliability, which implies the metric is robust against measurement noise and/or disturbances. Since the metrics have been used on different measuring instruments, the sensors’ resolution and signal-to-noise ratio appear to have a minimal impact on the reliability. However, more investigation is needed to confirm this robustness. In lieu of more evidence, it is recommended that investigators choose sensors similar or superior in quality to those used in the measuring devices presented in Tables 7 and 8 to achieve the same level of reliability.

What aspects of biomechanical-based metrics lack evidence or require more investigation?

Although many metrics (see previous section) demonstrate good or excellent repeatability across multiple studies, the evidence for reproducibility is limited to single studies. When developing a novel device capable of robotic assistance and assessment, researchers have typically focused their efforts to create a device capable of repeatable and reliable measurements. However, since the person administering the test is using the device to measure the subject’s performance, the reproducibility of the metric must also be considered. The reproducibility of a metric is affected by the ease-of-use of the device; if the device is too complicated to setup and use, there is an increased probability that different operators will observe different measurements. Also, the operator’s instructions to the subject affects the reproducibility, especially in the initial sessions, which may lead to different learning effects, and different assessment results. More studies are needed across multiple sites and operators to determine the reproducibility of the biomechanical metrics reviewed in this paper.

Which neural activity-based metrics (EEG & EMG) show the most promise for reliable assessment?

Electrical neurological signals such as EEG and EMG have successfully been used to understand changes in motor performance and outcome variability across all stages of post-stroke recovery including the first few hours after onset. Experimental results have shown that metrics derived from slow frequency power (delta power, relative delta power, and theta power), and power ratio between slow and fast EEG frequency bands like DAR and DTABR convey useful information both about current and future motor capabilities, as presented in Table 4 and Table 11 in Appendix 1. Multimodal studies using robotic tools for assessment of motor performance have expanded the study of power signal features in people who suffered a stroke in the chronic recovery stage by studying not only rest EEG activity but also task-related activity [ 19 , 21 , 122 ]; ERD-ERS features like amplitude and latency along with biomechanical measures have been shown to correlate with clinical measures of motor performance and to predict a person’s response to movement therapies. EEG power features in general have been found to have good to excellent reliability for test–retest conditions among different populations, across all frequency bands of interest (see Table 9 ).

Functional connectivity (i.e., non-directed connectivity) expands the investigative capacity of EEG measurements, enabling analyzing the brain as a network system by investigating the interactions between regions of interest in the brain while resting or during movement tasks. Inter-hemispheric interactions (interactions between the same ROI in both hemispheres) and global interactions (interactions between the entire brain and an ROI) reported as power or graph indices in Beta and Gamma bands have fruitfully been used to explain motor outcome scores. Although results seem promising, connectivity reliability is still debated with results ranging mostly between moderate to good reliability only for a few connectivity estimators ( PLI, wPLI and iCoh ).

Which neural activity-based metrics (EEG and EMG) lack evidence or require more investigation?

EEG and EMG provide useful non-invasive insight into the human neuromuscular system allowing researchers to make conjectures about its function and structure; however, interpretation of results based on these measures solely must be carefully analyzed within the frame of experimental conditions. Overall, the field needs more studies involving cohorts of stroke survivors to determine the reliability (test–retest) of metrics derived from EEG and EMG signal features that have already shown validity in academic studies.

Metrics calculated from power imbalance between interhemispheric activity like BSI , pwBSI and PRI [ 62 , 73 , 124 ] are a great premise to measure how the brain relies on foreign regions to accomplish tasks related with affected areas. A battery of diverse estimators for connectivity, especially those of effective (directed) connectivity, open the door to investigations into the relationship between abnormal communication of regions of interest and impairment (see Table 5 and Table 12 in Appendix 2). These metrics, although valid have yet to be tested in terms of reliability in clinical use. Reliability for connectivity metrics should specify which estimator was used to derive the metric.

CMC is another exciting neural-activity-based metric lacking sufficient evidence to support its significance. CMC considers and bridges two of the most affected domains for motor execution in neuromuscular system, making it a good candidate for robotic-based therapy and assessment of survivors of stroke [ 147 ]. Although features in the Beta and Gamma bands seem to be related to motor impairment, there is still not agreement about which one is most closely related to motor outcomes. Studies reviewed in this paper considered cortical spatial patterns of maximum coherence, peak frequency shift when compared to healthy controls, latency for peak coherence, among others (see Table 6 and Table 13 in Appendix 3). However, when comparing to motor outcomes, results are not always significant, and test–retest reliability for this metric is yet (to our knowledge) to be documented for the upper extremity (see [ 61 ] for a lower-extremity study).

What standards should be adopted for reporting biomechanical and neural activity-based metrics and their reliability?

For metrics to be accepted as reliable in the clinical field, researchers are asked to follow the guidelines presented in Koo and Li [ 68 ], which provide guidance on which ICC model to use depending on the type of reliability study and what should be reported (e.g., the software they used to compute the ICC and confidence interval). In the papers reviewed, some investigated the learning effects of the assessment task and checked for consistency rather than agreement (see Table 7 ). However, the learning effects should be minimal in a clinical setting between each session, and potential effects should be taken into consideration during protocol design; common practices to minimize the implications of learning effects is to allow practice runs by the patients [ 99 , 122 ] and to remove the first experimental runs [ 81 , 85 ]. By removing this information, signal analysis focuses performance of learned tasks with similar associated behaviors. Therefore, to demonstrate test–retest reliability (i.e., repeatability), the researcher should be checking for absolute agreement. Also, as can be seen in Tables 7 and 8 , there does not seem to be a standard on reporting ICC values. Some researchers report the confidence interval of the ICC value, while others do not. It was also difficult to determine the ICC model used in some of the studies. Therefore, a standard on reporting ICC values is needed to help readers understand the ICC used and prevent bias (see [ 68 ] for suggestive guideline on how to report ICC scores). Also, authors are asked to include the means of each individual session or rater would provide additional information on the variation of the means between the groups. The variation between groups can be shown with Bland–Altman plot, but readers are unable to perform other forms of analysis. To help with this, data from studies should be made publicly available to allow results to be verified and enable further analysis in the future.

When is it advantageous to combine biomechanical and neural activity-based metrics for assessment?

Biomechanical and neural activity provide distinct but complementary information about the neuro-musculoskeletal system, potentially offering a more complete picture of impairment and function after stroke. Metrics derived from kinematic/kinetic information assess motor performance based on motor execution; however, compensatory strategies related to stroke may mask underlying neural deficits (i.e., muscle synergies line up to complete a given task) [ 18 , 21 , 69 , 70 , 71 , 72 , 122 ]. Information relevant to these compensatory strategies can be obtained when analyzing electrophysiological activity, as has been done using connectivity [ 59 , 107 ], CMC [ 147 , 148 ] and brain cortical power [ 91 ].

Combining signals from multiple domains, although beneficial in the sense that it would allow a deeper understanding of a subject’s motor ability, is still a subject of exploration. Experimental paradigms play an important role that influences the decision of feature selection; increasing the dimensionality of signals may provide more useful information for analysis, but comes at the expense of experimental costs (e.g., hardware) and time (e.g., subject setup). With all this in mind, merging information from different domains in the hierarchy of the neuro-musculoskeletal system may provide a more comprehensive quantitative profile of a person’s impairment and performance. Examples of robotic multidomain methods such as the ones in [ 18 , 21 ], highlight the importance of this type of assessment for monitoring and understanding the impact of rehabilitation in chronic stroke survivors. In both cases, these methodologies allowed pairing of observed behavioral changes in task execution (i.e., biomechanical data) with corresponding functional recovery, instead of adopted compensation strategies.

What should be the focus of future investigations of biomechanical and/or neural activity-based metrics?

Determining the reliability and validity of sensor-based metrics requires carefully designed experiments. In future investigations, experiments should be conducted that calculate multiple metrics from multiple sensors and device combinations, allowing the effect of sensor type and quality on the measure’s reliability to be quantified. After the conclusion of such experiments, researchers are strongly encouraged to make their anonymized raw data public to allow other researchers to compute different ICCs. Performing comparison studies on the reliability of metrics will produce reliability data to expand Tables 7 , 8 , 9 and improve our ability to compare similar sensor-based metrics. Additional reliability studies should also be performed that include neural features of survivors of stroke, with increased focus on modeling the interactions between these domains (biomechanical and neural activity). It is also important to understand how to successfully combine data from multimodal experiments; many of the studies reviewed in this paper recorded multidimensional data, but performed analysis for each domain separately.

Availability of data and materials

Not applicable.

Abbreviations

Activities of daily living

Amplitude envelope correlation

Action research arm test

Active range of motion

Autism spectrum disorder

Box and Blocks test

Brain Symmetry Index

Canonical correlation analysis

Cortico-spinal tract

Delta-alpha ratio

Delayed cerebral ischemia

Direct directed transfer function

Degree of freedom

(Delta + Theta)/(Alpha + Beta)

Directed transfer function

Delta-theta ratio

Electroencephalography

Electromyography

Event related desynchronization

Event related synchronization

Full frequency directed transfer function

Functional independence measure and functional assessment measure

Fugl-Meyer assessment for upper extremity

Generalized Measure of Association

Generalized partial directed coherence

Intra-class correlations

Imaginary part of coherence

Primary motor cortex

Modified Ashworth

Modified Barthel Index

Multiple coherence

Motricity Index

Montreal Cognitive Assessment

Movement related beta desynchronization

Magnetic resonance imaging

Modified Ranking Scale

Normalized interhemispheric strength

National Institutes of Health Stroke Scale

Non-negative matrix factorization algorithm

Principal component analysis

Partial coherence

Partial directed coherence

Phase lag index, weight phase lag index, debiased weighted phase lag index

Premotor area

Post movement beta rebound

Power Ratio Index

Passive range of motion

Quantitative EEG

Regional cerebral blood flow

Region of interest

Renormalized partial directed coherence

Singular value decomposition

Wolf motor function

Weighted Node Degree Index

Stroke Facts. 2020. https://www.cdc.gov/stroke/facts.htm . Accessed 26 Mar 2020.

Ottenbacher KJ, Smith PM, Illig SB, Linn RT, Ostir GV, Granger CV. Trends in length of stay, living setting, functional outcome, and mortality following medical rehabilitation. JAMA. 2004;292(14):1687–95. https://doi.org/10.1001/jama.292.14.1687 .

Article CAS PubMed Google Scholar

Lang CE, MacDonald JR, Gnip C. Counting repetitions: an observational study of outpatient therapy for people with hemiparesis post-stroke. J Neurol Phys Ther. 2007;31(1). https://journals.lww.com/jnpt/Fulltext/2007/03000/Counting_Repetitions__An_Observational_Study_of.4.aspx .

Gresham GE, Phillips TF, Wolf PA, McNamara PM, Kannel WB, Dawber TR. Epidemiologic profile of long-term stroke disability: the Framingham study. Arch Phys Med Rehabil. 1979;60(11):487–91.

CAS PubMed Google Scholar

Duncan EA, Murray J. The barriers and facilitators to routine outcome measurement by allied health professionals in practice: a systematic review. BMC Health Serv Res. 2012;12(1):96.

Article PubMed PubMed Central Google Scholar

Sullivan KJ, Tilson JK, Cen SY, Rose DK, Hershberg J, Correa A, et al. Fugl-meyer assessment of sensorimotor function after stroke: standardized training procedure for clinical practice and clinical trials. Stroke. 2011;42(2):427–32.

Article PubMed Google Scholar

Ansari NN, Naghdi S, Arab TK, Jalaie S. The interrater and intrarater reliability of the Modified Ashworth Scale in the assessment of muscle spasticity: limb and muscle group effect. NeuroRehabilitation. 2008;23:231–7.

Wade DT, Collin C. The Barthel ADL Index: a standard measure of physical disability? Int Disabil Stud. 1988;10(2):64–7.

Maggioni S, Melendez-Calderon A, van Asseldonk E, Klamroth-Marganska V, Lünenburger L, Riener R, et al. Robot-aided assessment of lower extremity functions: a review. J Neuroeng Rehabil. 2016;13(1):72. https://doi.org/10.1186/s12984-016-0180-3 .

Frisoli A, Procopio C, Chisari C, Creatini I, Bonfiglio L, Bergamasco M, et al. Positive effects of robotic exoskeleton training of upper limb reaching movements after stroke. J Neuroeng Rehabil. 2012;9(1):36. https://doi.org/10.1186/1743-0003-9-36 .

Groothuis-Oudshoorn CGM, Prange GB, Hermens HJ, Ijzerman MJ, Jannink MJA. Systematic review of the effect of robot-aided therapy on recovery of the hemiparetic arm after stroke. J Rehabil Res Dev. 2006;43(2):171.

Harwin WS, Murgia A, Stokes EK. Assessing the effectiveness of robot facilitated neurorehabilitation for relearning motor skills following a stroke. Med Biol Eng Comput. 2011;49(10):1093–102.

Nordin N, Xie SQ, Wünsche B. Assessment of movement quality in robot- assisted upper limb rehabilitation after stroke: a review. J NeuroEngineering Rehabil. 2014;11:137. https://doi.org/10.1186/1743-0003-11-137 .

Article Google Scholar

De Los Reyes-Guzman A, Dimbwadyo-Terrer I, Trincado-Alonso F, Monasterio-Huelin F, Torricelli D, Gil-Agudo A. Quantitative assessment based on kinematic measures of functional impairments during upper extremity movements: a review. Clin Biomech. 2014;29(7):719–27. https://doi.org/10.1016/j.clinbiomech.2014.06.013 .

Molteni E, Preatoni E, Cimolin V, Bianchi AM, Galli M, Rodano R. A methodological study for the multifactorial assessment of motor adaptation: integration of kinematic and neural factors. 2010 Annu Int Conf IEEE Eng Med Biol Soc EMBC’10. 2010;4910–3.

Mazzoleni S, Coscia M, Rossi G, Aliboni S, Posteraro F, Carrozza MC. Effects of an upper limb robot-mediated therapy on paretic upper limb in chronic hemiparetic subjects: a biomechanical and EEG-based approach for functional assessment. 2009 IEEE Int Conf Rehabil Robot ICORR 2009. 2009;92–7.

Úbeda A, Azorín JM, Chavarriaga R, Millán JdR. Classification of upper limb center-out reaching tasks by means of EEG-based continuous decoding techniques. J Neuroeng Rehabil. 2017;14(1):1–14.

Pierella C, Pirondini E, Kinany N, Coscia M, Giang C, Miehlbradt J, et al. A multimodal approach to capture post-stroke temporal dynamics of recovery. J Neural Eng. 2020;17(4): 045002.

Steinisch M, Tana MG, Comani S. A post-stroke rehabilitation system integrating robotics, VR and high-resolution EEG imaging. IEEE Trans Neural Syst Rehabil Eng. 2013;21(5):849–59. https://doi.org/10.1596/978-1-4648-1002-2_Module14 .

Úbeda A, Hortal E, Iáñez E, Perez-Vidal C, Azorín JM. Assessing movement factors in upper limb kinematics decoding from EEG signals. PLoS ONE. 2015;10(5):1–12.

Belfatto A, Scano A, Chiavenna A, Mastropietro A, Mrakic-Sposta S, Pittaccio S, et al. A multiparameter approach to evaluate post-stroke patients: an application on robotic rehabilitation. Appl Sci. 2018;8(11):2248.

Comani S, Schinaia L, Tamburro G, Velluto L, Sorbi S, Conforto S, et al. Assessing Neuromotor Recovery in a stroke survivor with high resolution EEG, robotics and virtual reality. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). 2015. p. 3925–8.

Kwon HM, Yang IH, Lee WS, Yu ARL, Oh SY, Park KK. Reliability of intraoperative knee range of motion measurements by goniometer compared with robot-assisted arthroplasty. J Knee Surg. 2019;32(3):233–8.

Dukelow SP, Herter TM, Moore KD, Demers MJ, Glasgow JI, Bagg SD, et al. Quantitative assessment of limb position sense following stroke. Neurorehabil Neural Repair. 2010;24(2):178–87.

Balasubramanian S, Wei R, Herman R, He J. Robot-measured performance metrics in stroke rehabilitation. In: 2009 ICME International Conference on Complex Medical Engineering, CME 2009. 2009.

Otaka E, Otaka Y, Kasuga S, Nishimoto A, Yamazaki K, Kawakami M, et al. Clinical usefulness and validity of robotic measures of reaching movement in hemiparetic stroke patients. J Neuroeng Rehabil. 2015;12(1):66.

Singh H, Unger J, Zariffa J, Pakosh M, Jaglal S, Craven BC, et al. Robot-assisted upper extremity rehabilitation for cervical spinal cord injuries: a systematic scoping review. Disabil Rehabil Assist Technol. 2018;13(7):704–15. https://doi.org/10.1080/17483107.2018.1425747 .

Molteni F, Gasperini G, Cannaviello G, Guanziroli E. Exoskeleton and end-effector robots for upper and lower limbs rehabilitation: narrative review. PMR. 2018;10(9):174–88.

Jutinico AL, Jaimes JC, Escalante FM, Perez-Ibarra JC, Terra MH, Siqueira AAG. Impedance control for robotic rehabilitation: a robust markovian approach. Front Neurorobot. 2017;11(AUG):1–16.

Google Scholar

Li Z, Huang Z, He W, Su CY. Adaptive impedance control for an upper limb robotic exoskeleton using biological signals. IEEE Trans Ind Electron. 2017;64(2):1664–74.

Marchal-Crespo L, Reinkensmeyer DJ. Review of control strategies for robotic movement training after neurologic injury. J NeuroEngineering Rehabil. 2009;6:20. https://doi.org/10.1186/1743-0003-6-20 .

Cohen MX. Analyzing neural time series data: theory and practice. Cambridge: MIT Press; 2014.

Book Google Scholar

Stafstrom CE, Carmant L. Seizures and epilepsy: an overview. Cold Spring Harb Perspect Med. 2015;5(6):65–77.

Machado C, Cuspineda E, Valdãs P, Virues T, Liopis F, Bosch J, et al. Assessing acute middle cerebral artery ischemic stroke by quantitative electric tomography. Clin EEG Neurosci. 2004;35(3):116–24.

Finnigan SP, Walsh M, Rose SE, Chalk JB. Quantitative EEG indices of sub-acute ischaemic stroke correlate with clinical outcomes. Clin Neurophysiol. 2007;118(11):2525–31.

Cuspineda E, Machado C, Galán L, Aubert E, Alvarez MA, Llopis F, et al. QEEG prognostic value in acute stroke. Clin EEG Neurosci. 2007;38(3):155–60.

Belardinelli P, Laer L, Ortiz E, Braun C, Gharabaghi A. Plasticity of premotor cortico-muscular coherence in severely impaired stroke patients with hand paralysis. NeuroImage Clin. 2017;14:726–33.

Di PM, Schnider A, Nicolo P, Rizk S, Guggisberg AG. Coherent neural oscillations predict future motor and language improvement after stroke. Brain. 2015;138(10):3048–60.

Chen CC, Lee SH, Wang WJ, Lin YC, Su MC. EEG-based motor network biomarkers for identifying target patients with stroke for upper limb rehabilitation and its construct validity. PLoS ONE. 2017;12(6):1–20. https://doi.org/10.1371/journal.pone.0178822 .

Article CAS Google Scholar

Conway BA, Halliday DM, Farmer SF, Shahani U, Maas P, Weir AI, et al. Synchronization between motor cortex and spinal motoneuronal pool during the performance of a maintained motor task in man. J Physiol. 1995;489(3):917–24.

Article CAS PubMed PubMed Central Google Scholar

Salenius S, Portin K, Kajola M, Salmelin R, Hari R. Cortical control of human motoneuron firing during isometric contraction. J Neurophysiol. 1997;77(6):3401–5.

Mima T, Hallett M. Electroencephalographic analysis of cortico-muscular coherence: reference effect, volume conduction and generator mechanism. Clin Neurophysiol. 1999;110(11):1892–9.

Claassen J, Hirsch LJ, Kreiter KT, Du EY, Sander Connolly E, Emerson RG, et al. Quantitative continuous EEG for detecting delayed cerebral ischemia in patients with poor-grade subarachnoid hemorrhage. Clin Neurophysiol. 2004;115(12):2699–710.

Sullivan JL, Bhagat NA, Yozbatiran N, Paranjape R, Losey CG, Grossman RG, et al. Improving robotic stroke rehabilitation by incorporating neural intent detection: preliminary results from a clinical trial. In: 2017 International Conference on Rehabilitation Robotics (ICORR). IEEE; 2017. p. 122–7.

Muralidharan A, Chae J, Taylor DM. Extracting attempted hand movements from EEGs in people with complete hand paralysis following stroke. Front Neurosci. 2011. https://doi.org/10.3389/fnins.2011.00039 .

Nam C, Rong W, Li W, Xie Y, Hu X, Zheng Y. The effects of upper-limb training assisted with an electromyography-driven neuromuscular electrical stimulation robotic hand on chronic stroke. Front Neurol. 2017. https://doi.org/10.3389/fneur.2017.00679 .

Bertolucci F, Lamola G, Fanciullacci C, Artoni F, Panarese A, Micera S, et al. EEG predicts upper limb motor improvement after robotic rehabilitation in chronic stroke patients. Ann Phys Rehabil Med. 2018;61:e200–1.

Cantillo-Negrete J, Carino-Escobar RI, Carrillo-Mora P, Elias-Vinas D, Gutierrez-Martinez J. Motor imagery-based brain-computer interface coupled to a robotic hand orthosis aimed for neurorehabilitation of stroke patients. J Healthc Eng. 2018;3(2018):1–10.

Bhagat NA, Venkatakrishnan A, Abibullaev B, Artz EJ, Yozbatiran N, Blank AA, et al. Design and optimization of an EEG-based brain machine interface (BMI) to an upper-limb exoskeleton for stroke survivors. Front Neurosci. 2016;10(MAR):122.

PubMed PubMed Central Google Scholar

Biasiucci A, Leeb R, Iturrate I, Perdikis S, Al-Khodairy A, Corbet T, et al. Brain-actuated functional electrical stimulation elicits lasting arm motor recovery after stroke. Nat Commun. 2018;9(1):1–13. https://doi.org/10.1038/s41467-018-04673-z .

Ang KK, Guan C, Chua KSG, Ang BT, Kuah C, Wang C, et al. Clinical study of neurorehabilitation in stroke using EEG-based motor imagery brain-computer interface with robotic feedback. Annu Int Conf IEEE Eng Med Biol. 2010. pp. 5549–52.

Finnigan SP, Rose SE, Walsh M, Griffin M, Janke AL, Mcmahon KL, et al. Correlation of quantitative EEG in acute ischemic stroke with 30-day NIHSS score: comparison with diffusion and perfusion MRI. Stroke. 2004;35(4):899–903.

Schleiger E, Sheikh N, Rowland T, Wong A, Read S, Finnigan S. Frontal EEG delta / alpha ratio and screening for post-stroke cognitive de fi cits: the power of four electrodes. Int J Psychophysiol. 2014;94(1):19–24. https://doi.org/10.1016/j.ijpsycho.2014.06.012 .

Aminov A, Rogers JM, Johnstone SJ, Middleton S, Wilson PH. Acute single channel EEG predictors of cognitive function after stroke. PLoS ONE. 2017;12(10): e0185841.

Andresen EM. Criteria for assessing the tools of disability outcomes research. Arch Phys Med Rehabil. 2000. https://doi.org/10.1053/apmr.2000.20619 .

Wang Q, Markopoulos P, Yu B, Chen W, Timmermans A. Interactive wearable systems for upper body rehabilitation: a systematic review. J Neuroeng Rehabil. 2017;14(1):1–21.

Tran VD, Dario P, Mazzoleni S. Kinematic measures for upper limb robot-assisted therapy following stroke and correlations with clinical outcome measures: a review. Med Eng Phys. 2018;53:13–31. https://doi.org/10.1016/j.medengphy.2017.12.005 .

Finnigan S, Wong A, Read S. Defining abnormal slow EEG activity in acute ischaemic stroke: Delta/alpha ratio as an optimal QEEG index. Clin Neurophysiol. 2016;127(2):1452–9. https://doi.org/10.1016/j.clinph.2015.07.014 .

Carter AR, Shulman GL, Corbetta M. Why use a connectivity-based approach to study stroke and recovery of function? Neuroimage. 2012;62(4):2271–80.

van der Velde B, Haartsen R, Kemner C. Test-retest reliability of EEG network characteristics in infants. Brain Behav. 2019;9(5):1–10.

Gennaro F, de Bruin ED. A pilot study assessing reliability and age-related differences in corticomuscular and intramuscular coherence in ankle dorsiflexors during walking. Physiol Rep. 2020;8(4):1–12.

Brihmat N, Loubinoux I, Castel-Lacanal E, Marque P, Gasq D. Kinematic parameters obtained with the ArmeoSpring for upper-limb assessment after stroke: a reliability and learning effect study for guiding parameter use. J Neuroeng Rehabil. 2020;17(1):130. https://doi.org/10.1186/s12984-020-00759-2 .

Dewald JPA, Ellis MD, Acosta AM, McPherson JG, Stienen AHA. Implementation of impairment- based neurorehabilitation devices and technologies following brain injury. Neurorehabilitation technology, 2nd edn. 2016. 375–392 p.

Subramanian SK, Yamanaka J, Chilingaryan G, Levin MF. Validity of movement pattern kinematics as measures of arm motor impairment poststroke. Stroke. 2010;41(10):2303–8.

Fayers PM, Machin D. Quality of life: the assessment, analysis and reporting of patient‐reported outcomes . John Wiley & Sons, Incorporated. 2016;3:89-124.

Alt Murphy M, Häger CK. Kinematic analysis of the upper extremity after stroke—how far have we reached and what have we grasped? Phys Ther Rev. 2015;20(3):137–55.

Shishov N, Melzer I, Bar-Haim S. Parameters and measures in assessment of motor learning in neurorehabilitation; a systematic review of the literature. Front Hum Neurosci. 2017. https://doi.org/10.3389/fnhum.2017.00082 .

Koo TK, Li MY. A guideline of selecting and reporting intraclass correlation coefficients for reliability research. J Chiropr Med. 2016;15(2):155–63. https://doi.org/10.1016/j.jcm.2016.02.012 .

Angel RW. Electromyographic patterns during ballistic movement of normal and spastic limbs. Brain Res. 1975;99(2):387–92.

McLellan DL. C0-contraction and stretch reflexes in spasticity during treatment with baclofen. J Neurol Neurosurg Psychiatry. 1977;40(1):30–8.

Dewald JPA, Pope PS, Given JD, Buchanan TS, Rymer WZ. Abnormal muscle coactivation patterns during isometric torque generation at the elbow and shoulder in hemiparetic subjects. Brain. 1995;118(2):495–510. https://doi.org/10.1093/brain/118.2.495 .

Wilkins KB, Yao J, Owen M, Karbasforoushan H, Carmona C, Dewald JPA. Limited capacity for ipsilateral secondary motor areas to support hand function post-stroke. J Physiol. 2020;598(11):2153–67. https://doi.org/10.1113/JP279377 .

Agius Anastasi A, Falzon O, Camilleri K, Vella M, Muscat R. Brain symmetry index in healthy and stroke patients for assessment and prognosis. Stroke Res Treat. 2017;30(2017):1–9.

Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis JPA, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. BMJ. 2009;339: b2700.

Colombo R, Pisano F, Micera S, Mazzone A, Delconte C, Carrozza MC, et al. Assessing mechanisms of recovery during robot-aided neurorehabilitation of the upper limb. Neurorehabil Neural Repair. 2008;22(1):50–63. https://doi.org/10.1177/1545968307303401 .

Keller U, Schölch S, Albisser U, Rudhe C, Curt A, Riener R, et al. Robot-assisted arm assessments in spinal cord injured patients: a consideration of concept study. PLoS One. 2015;10(5):e0126948. https://doi.org/10.1371/journal.pone.0126948 .

Mostafavi SM. Computational models for improved diagnosis and prognosis of stroke using robot-based biomarkers. 2016. http://hdl.handle.net/1974/14563 .

Bosecker C, Dipietro L, Volpe B, Krebs HI. Kinematic robot-based evaluation scales and clinical counterparts to measure upper limb motor performance in patients with chronic stroke. Neurorehabil Neural Repair. 2010;24(1):62–9.

Balasubramanian S, Melendez-Calderon A, Roby-Brami A, Burdet E. On the analysis of movement smoothness. J Neuroeng Rehabil. 2015;12(1):112. https://doi.org/10.1186/s12984-015-0090-9 .

Rohrer B, Fasoli S, Krebs HI, Hughes R, Volpe B, Frontera WR, et al. Movement smoothness changes during stroke recovery. J Neurosci. 2002;22(18):8297–304.

Mobini A, Behzadipour S, Saadat M. Test-retest reliability of Kinect’s measurements for the evaluation of upper body recovery of stroke patients. Biomed Eng Online. 2015;14(1):1–14.

Zariffa J, Myers M, Coahran M, Wang RH. Smallest real differences for robotic measures of upper extremity function after stroke: implications for tracking recovery. J Rehabil Assist Technol Eng. 2018;5:205566831878803. https://doi.org/10.1177/2055668318788036 .

Elovic E, Brashear A. Spasticity : diagnosis and management. New York: Demos Medical; 2011. http://ida.lib.uidaho.edu:2048/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=e000xna&AN=352265&site=ehost-live&scope=site .

Centen A, Lowrey CR, Scott SH, Yeh TT, Mochizuki G. KAPS (kinematic assessment of passive stretch): a tool to assess elbow flexor and extensor spasticity after stroke using a robotic exoskeleton. J Neuroeng Rehabil. 2017;14(1):1–13.

Sin M, Kim WS, Cho K, Cho S, Paik NJ. Improving the test-retest and inter-rater reliability for stretch reflex measurements using an isokinetic device in stroke patients with mild to moderate elbow spasticity. J Electromyogr Kinesiol. 2017;2018(39):120–7. https://doi.org/10.1016/j.jelekin.2018.01.012 .

Germanotta M, Cruciani A, Pecchioli C, Loreti S, Spedicato A, Meotti M, et al. Reliability, validity and discriminant ability of the instrumental indices provided by a novel planar robotic device for upper limb rehabilitation. J Neuroeng Rehabil. 2018;15(1):1–14.

Wagner JM, Rhodes JA, Patten C. Reproducibility and minimal detectable change of three-dimensional kinematic analysis of reaching tasks in people with hemiparaesis after stroke. 2008. https://doi.org/10.2522/ptj.20070255 .

Semrau JA, Herter TM, Scott SH, Dukelow SP. Inter-rater reliability of kinesthetic measurements with the KINARM robotic exoskeleton. J Neuroeng Rehabil. 2017;14(1):1–10.

Lin CH, Chou LW, Wei SH, Lieu FK, Chiang SL, Sung WH. Validity and reliability of a novel device for bilateral upper extremity functional measurements. Comput Methods Programs Biomed. 2014;114(3):315–23. https://doi.org/10.1016/j.cmpb.2014.02.012 .

Wolf S, Butler A, Alberts J, Kim M. Contemporary linkages between EMG, kinetics and stroke. J Electromyogr Kinesiol. 2005;15(3):229–39.

Iyer KK. Effective assessments of electroencephalography during stroke recovery : contemporary approaches and considerations. J Neurophysiol. 2017;118(5):2521–5.

Liu J, Sheng Y, Liu H. Corticomuscular coherence and its applications: a review. Front Hum Neurosci. 2019;13(March):1–16.

Pan LLH, Yang WW, Kao CL, Tsai MW, Wei SH, Fregni F, et al. Effects of 8-week sensory electrical stimulation combined with motor training on EEG-EMG coherence and motor function in individuals with stroke. Sci Rep. 2018;8(1):1–10.

Wu J, Quinlan EB, Dodakian L, McKenzie A, Kathuria N, Zhou RJ, et al. Connectivity measures are robust biomarkers of cortical function and plasticity after stroke. Brain. 2015;138(8):2359–69.

Mrachacz-Kersting N, Jiang N, Thomas Stevenson AJ, Niazi IK, Kostic V, Pavlovic A, et al. Efficient neuroplasticity induction in chronic stroke patients by an associative brain-computer interface. J Neurophysiol. 2016;115(3):1410–21.

Bentes C, Peralta AR, Viana P, Martins H, Morgado C, Casimiro C, et al. Quantitative EEG and functional outcome following acute ischemic stroke. Clin Neurophysiol. 2018;129(8):1680–7.

Leon-carrion J, Martin-rodriguez JF, Damas-lopez J, Manuel J, Dominguez-morales MR. Delta–alpha ratio correlates with level of recovery after neurorehabilitation in patients with acquired brain injury. Clin Neurophysiol. 2009;120(6):1039–45. https://doi.org/10.1016/j.clinph.2009.01.021 .

Finnigan S, van Putten MJAM. EEG in ischaemic stroke: qEEG can uniquely inform (sub-)acute prognoses and clinical management. Clin Neurophysiol. 2013;124(1):10–9.

Trujillo P, Mastropietro A, Scano A, Chiavenna A, Mrakic-Sposta S, Caimmi M, et al. Quantitative EEG for predicting upper limb motor recovery in chronic stroke robot-assisted rehabilitation. IEEE Trans Neural Syst Rehabil Eng. 2017;25(7):1058–67.

Jordan K. Emergency EEG and continuous EEG monitoring in acute ischemic stroke. Clin Neurophysiol. 2004;21(5):341–52.

Comani S, Velluto L, Schinaia L, Cerroni G, Serio A, Buzzelli S, et al. Monitoring neuro-motor recovery from stroke with high-resolution EEG, robotics and virtual reality: a proof of concept. IEEE Trans Neural Syst Rehabil Eng. 2015;23(6):1106–16.

Espenhahn S, de Berker AO, van Wijk BCM, Rossiter HE, Ward NS. Movement-related beta oscillations show high intra-individual reliability. Neuroimage. 2017;147:175–85. https://doi.org/10.1016/j.neuroimage.2016.12.025 .

Vázquez-Marrufo M, Galvao-Carmona A, Benítez Lugo ML, Ruíz-Peña JL, Borges Guerra M, Izquierdo AG. Retest reliability of individual alpha ERD topography assessed by human electroencephalography. PLoS ONE. 2017;12(10):1–16.

Dubovik S, Ptak R, Aboulafia T, Magnin C, Gillabert N, Allet L, et al. EEG alpha band synchrony predicts cognitive and motor performance in patients with ischemic stroke. In: Behavioural Neurology. Hindawi Limited; 2013. p. 187–9.

Sheorajpanday RVAA, Nagels G, Weeren AJTMTM, Putten MJAMV, Deyn PPD, van Putten MJAM, et al. Quantitative EEG in ischemic stroke: correlation with functional status after 6 months. Clin Neurophysiol. 2011;122(5):874–83. https://doi.org/10.1016/j.clinph.2010.07.028 .

De Vico Fallani F, Astolfi L, Cincotti F, Mattia D, La Rocca D, Maksuti E, et al. Evaluation of the brain network organization from EEG signals: a preliminary evidence in stroke patient. In: Anatomical Record. 2009. p. 2023–31.

Westlake KP, Nagarajan SS. Functional connectivity in relation to motor performance and recovery after stroke. Front Syst Neurosci. 2011;18(5):8.

Caliandro P, Vecchio F, Miraglia F, Reale G, Della Marca G, La Torre G, et al. Small-world characteristics of cortical connectivity changes in acute stroke. Neurorehabil Neural Repair. 2017;31(1):81–94.

Eldeeb S, Akcakaya M, Sybeldon M, Foldes S, Santarnecchi E, Pascual-Leone A, et al. EEG-based functional connectivity to analyze motor recovery after stroke: a pilot study. Biomed Signal Process Control. 2019;49:419–26.

Myers LJ, O’Malley M. The relationship between human cortico-muscular coherence and rectified EMG. In: International IEEE/EMBS Conference on Neural Engineering, NER. IEEE Computer Society; 2003. p. 289–92.

Braun C, Staudt M, Schmitt C, Preissl H, Birbaumer N, Gerloff C. Crossed cortico-spinal motor control after capsular stroke. Eur J Neurosci. 2007;25(9):2935–45.

Larsen LH, Zibrandtsen IC, Wienecke T, Kjaer TW, Christensen MS, Nielsen JB, et al. Corticomuscular coherence in the acute and subacute phase after stroke. Clin Neurophysiol. 2017;128(11):2217–26.

Ang KK, Chua KSG, Phua KS, Wang C, Chin ZY, Kuah CWK, et al. A randomized controlled trial of EEG-based motor imagery brain-computer interface robotic rehabilitation for stroke. Clin EEG Neurosci. 2015;46(4):310–20.

Liu S, Guo J, Meng J, Wang Z, Yao Y, Yang J, et al. Abnormal EEG complexity and functional connectivity of brain in patients with acute thalamic ischemic stroke. Comput Math Methods Med. 2016;14(2016):1–9.

CAS Google Scholar

Sun R, Wong W, Wang J, Tong RK. Changes in electroencephalography complexity using a brain computer interface-motor observation training in chronic stroke patients : a fuzzy approximate entropy analysis. Front Hum Neurosci. 2017;5(11):444.

Auriat AM, Neva JL, Peters S, Ferris JK, Boyd LA. A review of transcranial magnetic stimulation and multimodal neuroimaging to characterize post-stroke neuroplasticity. Front Neurol. 2015;6:1–20.

Niedermeyer E, Schomer DL, Lopes da Silva FH. Niedermeyer’s electroencephalography: basic principles, clinical applications, and related fields, 6th edn. Philadelphia: Lippincott Williams & Wilkins.; 2011.

Foreman B, Claasen J. Update in intensive care and emergency medicine. Update in intensive care and emergency medicine. Springer Berlin Heidelberg; 2012.

Tolonen U, Ahonen A, Kallanranta T, Hokkanen E. Non-invasive external regional measurement of cerebral circulation time changes in supratentorial infarctions using pertechnetate. Stroke. 1981;12(4):437–44.

Saes M, Zandvliet SB, Andringa AS, Daffertshofer A, Twisk JWR, Meskers CGM, et al. Is resting-state EEG longitudinally associated with recovery of clinical neurological impairments early poststroke? A prospective cohort study. Neurorehabil Neural Repair. 2020;34(5):389–402.

Rogers J, Middleton S, Wilson PH, Johnstone SJ. Predicting functional outcomes after stroke: an observational study of acute single-channel EEG. Top Stroke Rehabil. 2020;27(3):161–72. https://doi.org/10.1080/10749357.2019.1673576 .

Sale P, Infarinato F, Lizio R, Babiloni C. Electroencephalographic markers of robot-aided therapy in stroke patients for the evaluation of upper limb rehabilitation. Rehabil Res. 2015;38(4):294–305.

Sheorajpanday RVA, Nagels G, Weeren AJTM, De Surgeloose D, De Deyn PP, De DPP. Additional value of quantitative EEG in acute anterior circulation syndrome of presumed ischemic origin. Clin Neurophysiol. 2010;121(10):1719–25.

Saes M, Meskers CGM, Daffertshofer A, van Wegen EEH, Kwakkel G. Are early measured resting-state EEG parameters predictive for upper limb motor impairment six months poststroke? Clin Neurophysiol. 2021;132(1):56–62. https://doi.org/10.1016/j.clinph.2020.09.031 .

Saes M, Meskers CGM, Daffertshofer A, de Munck JC, Kwakkel G, van Wegen EEH. How does upper extremity Fugl-Meyer motor score relate to resting-state EEG in chronic stroke? A power spectral density analysis. Clin Neurophysiol. 2019;130(5):856–62. https://doi.org/10.1016/j.clinph.2019.01.007 .

Nolte G, Bai O, Mari Z, Vorbach S, Hallett M. Identifying true brain interaction from EEG data using the imaginary part of coherency. Clin Neurophysiol. 2004;115(10):2292–307.

Stam CJ, Nolte G, Daffertshofer A. Phase lag index: assessment of functional connectivity from multi channel EEG and MEG with diminished bias from common sources. Hum Brain Mapp. 2007;28(11):1178–93.

Bullmore E, Sporns O. Complex brain networks: graph theoretical analysis of structural and functional systems. Nat Rev Neurosci. 2009;10(3):186–98.

Baccalá LA, Sameshima K. Partial directed coherence: a new concept in neural structure determination. Biol Cybern. 2001;84(6):463–74.

Baccalá LA, Sameshima K, Takahashi D. Generalized partial directed coherence. Int Conf Digit Signal Process. 2007;3:163–6.

Schelter B, Timmer J, Eichler M. Assessing the strength of directed influences among neural signals using renormalized partial directed coherence. J Neurosci Methods. 2009;179(1):121–30.

Kamiński M, Ding M, Truccolo WA, Bressler SL. Evaluating causal relations in neural systems: Granger causality, directed transfer function and statistical assessment of significance. Biol Cybern. 2001;85(2):145–57.

Korzeniewska A, Mańczak M, Kamiński M, Blinowska KJ, Kasicki S. Determination of information flow direction among brain structures by a modified directed transfer function (dDTF) method. J Neurosci Methods. 2003;125(1–2):195–207.

Fornito A, Bullmore ET, Zalesky A. Fundamentals of brain network analysis. Cambridge: Academic Press; 2016.

Philips GR, Daly JJ, Príncipe JC. Topographical measures of functional connectivity as biomarkers for post-stroke motor recovery. J Neuroeng Rehabil. 2017;14(1):67.

Pichiorri F, Petti M, Caschera S, Astolfi L, Cincotti F, Mattia D. An EEG index of sensorimotor interhemispheric coupling after unilateral stroke: clinical and neurophysiological study. Eur J Neurosci. 2018;47(2):158–63.

Hoshino T, Oguchi K, Inoue K, Hoshino A, Hoshiyama M. Relationship between upper limb function and functional neural connectivity among motor related-areas during recovery stage after stroke. Top Stroke Rehabil. 2020;27(1):57–66. https://doi.org/10.1080/10749357.2019.1658429 .

Hordacre B, Goldsworthy MR, Welsby E, Graetz L, Ballinger S, Hillier S. Resting state functional connectivity is associated with motor pathway integrity and upper-limb behavior in chronic stroke. Neurorehabil Neural Repair. 2020;34(6):547–57.

Riahi N, Vakorin VA, Menon C. Estimating Fugl-Meyer upper extremity motor score from functional-connectivity measures. IEEE Trans Neural Syst Rehabil Eng. 2020;28(4):860–8.

Gwin JT, Ferris DP. Beta- and gamma-range human lower limb corticomuscular coherence. Front Hum Neurosci. 2012;11(6):258.

Zheng Y, Peng Y, Xu G, Li L, Wang J. Using corticomuscular coherence to reflect function recovery of paretic upper limb after stroke: a case study. Front Neurol. 2018;10(8):728.

Rossiter HE, Eaves C, Davis E, Boudrias MH, Park CH, Farmer S, et al. Changes in the location of cortico-muscular coherence following stroke. NeuroImage Clin. 2013;2(1):50–5.

Mima T, Toma K, Koshy B, Hallett M. Coherence between cortical and muscular activities after subcortical stroke. Stroke. 2001;32(11):2597–601.

Krauth R, Schwertner J, Vogt S, Lindquist S, Sailer M, Sickert A, et al. Cortico-muscular coherence is reduced acutely post-stroke and increases bilaterally during motor recovery: a pilot study. Front Neurol. 2019;20(10):126.

Bao SC, Wong WW, Leung TW, Tong KY. Low gamma band cortico-muscular coherence inter-hemisphere difference following chronic stroke. In: Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS. Institute of Electrical and Electronics Engineers Inc.; 2018. p. 247–50.

von Carlowitz-Ghori K, Bayraktaroglu Z, Hohlefeld FU, Losch F, Curio G, Nikulin VV. Corticomuscular coherence in acute and chronic stroke. Clin Neurophysiol. 2014;125(6):1182–91.

Chen X, Xie P, Zhang Y, Chen Y, Cheng S, Zhang L. Abnormal functional corticomuscular coupling after stroke. NeuroImage Clin. 2018;19:147–59. https://doi.org/10.1016/j.nicl.2018.04.004 .

Curado MR, Cossio EG, Broetz D, Agostini M, Cho W, Brasil FL, et al. Residual upper arm motor function primes innervation of paretic forearm muscles in chronic stroke after brain-machine interface (BMI) training. PLoS ONE. 2015;10(10):1–18.

Guo Z, Qian Q, Wong K, Zhu H, Huang Y, Hu X, et al. Altered corticomuscular coherence (CMCoh) pattern in the upper limb during finger movements after stroke. Front Neurol. 2020. https://doi.org/10.3389/fneur.2020.00410 .

Bruton A, Conway JH, Holgate ST. Reliability: what is it, and how is it measured? Physiotherapy. 2000;86(2):94–9.

Colombo R, Cusmano I, Sterpi I, Mazzone A, Delconte C, Pisano F. Test-retest reliability of robotic assessment measures for the evaluation of upper limb recovery. IEEE Trans Neural Syst Rehabil Eng. 2014;22(5):1020–9.

Costa V, Ramírez Ó, Otero A, Muñoz-García D, Uribarri S, Raya R. Validity and reliability of inertial sensors for elbow and wrist range of motion assessment. PeerJ. 2020;8: e9687.

Gasser T, Bächer P, Steinberg H. Test-retest reliability of spectral parameters of the EEG. Electroencephalogr Clin Neurophysiol. 1985;60(4):312–9.

Levin AR, Naples AJ, Scheffler AW, Webb SJ, Shic F, Sugar CA, et al. Day-to-day test-retest reliability of EEG profiles in children with autism spectrum disorder and typical development. Front Integr Neurosci. 2020;14:1–12.

Briels CT, Briels CT, Schoonhoven DN, Schoonhoven DN, Stam CJ, De Waal H, et al. Reproducibility of EEG functional connectivity in Alzheimer’s disease. Alzheimer’s Res Ther. 2020;12(1):1–14.

Marquetand J, Vannoni S, Carboni M, Li Hegner Y, Stier C, Braun C, et al. Reliability of magnetoencephalography and high-density electroencephalography resting-state functional connectivity metrics. Brain Connect. 2019;9(7):539–53.

Lowrey CR, Blazevski B, Marnet J-L, Bretzke H, Dukelow SP, Scott SH. Robotic tests for position sense and movement discrimination in the upper limb reveal that they each are highly reproducible but not correlated in healthy individuals. J Neuroeng Rehabil. 2020;17(1):103. https://doi.org/10.1186/s12984-020-00721-2 .

Simmatis LER, Early S, Moore KD, Appaqaq S, Scott SH. Statistical measures of motor, sensory and cognitive performance across repeated robot-based testing. J Neuroeng Rehabil. 2020;17(1):86. https://doi.org/10.1186/s12984-020-00713-2 .

Download references

Acknowledgements

The authors would like to thank Stephen Goodwin and Aaron I. Feinstein for their contributions to the collection and organization of references on robotic systems, measurements, and metrics.

This work was funded by the National Science Foundation (Award#1532239) and the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health (Award#K12HD073945). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Science Foundation nor the National Institutes of Health.

Author information

Authors and affiliations.

Mechanical Engineering Department, University of Idaho, Moscow, ID, USA

Rene M. Maura, Eric T. Wolbrecht & Joel C. Perry

Engineering and Physics Department, Whitworth University, Spokane, WA, USA

Richard E. Stevens

College of Medicine, Washington State University, Spokane, WA, USA

Douglas L. Weeks

Electrical Engineering Department, University of Idaho, ID, Moscow, USA

Sebastian Rueda Parra

You can also search for this author in PubMed Google Scholar

Contributions

RM, and SRP drafted the manuscript and performed the literature search. EW, JP, RS, and DW provided concepts, edited, and revised the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Rene M. Maura .

Ethics declarations

Ethics approval and consent to participate, consent for publication, competing interests.

The authors declare that they have no competing interests.

Additional information

Publisher's note.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

See Table 11 .

See Table 12 .

See Table 13 .

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ . The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/ ) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Cite this article.

Maura, R.M., Rueda Parra, S., Stevens, R.E. et al. Literature review of stroke assessment for upper-extremity physical function via EEG, EMG, kinematic, and kinetic measurements and their reliability. J NeuroEngineering Rehabil 20 , 21 (2023). https://doi.org/10.1186/s12984-023-01142-7

Download citation

Received : 27 May 2021

Accepted : 19 January 2023

Published : 15 February 2023

DOI : https://doi.org/10.1186/s12984-023-01142-7

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Reliability
Robot-assisted therapy
Exoskeleton
Neurological assessment
Rehabilitation
Motor function

Journal of NeuroEngineering and Rehabilitation

ISSN: 1743-0003

Submission enquiries: [email protected]

Organizing Academic Research Papers: 5. The Literature Review

Purpose of Guide
Design Flaws to Avoid
Glossary of Research Terms
Narrowing a Topic Idea
Broadening a Topic Idea
Extending the Timeliness of a Topic Idea
Academic Writing Style
Choosing a Title
Making an Outline
Paragraph Development
Executive Summary
Background Information
The Research Problem/Question
Theoretical Framework
Citation Tracking
Content Alert Services
Evaluating Sources
Primary Sources
Secondary Sources
Tertiary Sources
What Is Scholarly vs. Popular?
Qualitative Methods
Quantitative Methods
Using Non-Textual Elements
Limitations of the Study
Common Grammar Mistakes
Avoiding Plagiarism
Footnotes or Endnotes?
Further Readings
Annotated Bibliography
Dealing with Nervousness
Using Visual Aids
Grading Someone Else's Paper
How to Manage Group Projects
Multiple Book Review Essay
Reviewing Collected Essays
About Informed Consent
Writing Field Notes
Writing a Policy Memo
Writing a Research Proposal
Acknowledgements

A literature review surveys scholarly articles, books and other sources relevant to a particular issue, area of research, or theory, and by so doing, providing a description, summary, and critical evaluation of these works. Literature reviews are designed to provide an overview of sources you have explored while researching a particular topic and to demonstrate to your readers how your research fits into the larger field of study.

Importance of a Good Literature Review

A literature review may consist of simple a summary of key sources, but it usually has an organizational pattern and combines both summary and synthesis, often within specific conceptual categories . A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information in a way that informs how you are planning to investigate a research problem. The analytical features of a literature review might:

Give a new interpretation of old material or combine new with old interpretations,
Trace the intellectual progression of the field, including major debates,
Depending on the situation, evaluate the sources and advise the reader on the most pertinent or relevant, or
Usually in the conclusion of a literature review, identify where gaps exist in how a problem has been researched to date.

The purpose of a literature review is to:

Place each work in the context of its contribution to the understanding of the research problem being studied,
Describe the relationship of each work to the others under consideration,
Identify new ways to interpret, and shed light on any gaps in previous research,
Resolve conflicts amongst seemingly contradictory previous studies,
Identify areas of prior scholarship to prevent duplication of effort,
Point the way in fulfilling a need for additional research, and
Locate your own research within the context of existing literature.

Types of Literature Reviews

It is important to think of knowledge in a given field as consisting of three layers.* First, there are the primary studies that researchers conduct and publish. Second are the reviews of those studies that summarize and offer new interpretations built from and often extending beyond the original studies. Third, there are the perceptions, conclusions, opinion, and interpretations that are shared informally that become part of the lore of field. In composing a literature review, it is important to note that it is often this third layer of knowledge that is cited as "true" even though it often has only a loose relationship to the primary studies and secondary literature reviews. Given this, while literature reviews are designed to provide an overview and synthesis of pertinent sources you have explored, there are a number of approaches you could adopt depending upon the type of analysis underpinning your study.

Integrative Review Considered a form of research that reviews, critiques, and synthesizes representative literature on a topic in an integrated way such that new frameworks and perspectives on the topic are generated. The body of literature includes all studies that address related or identical hypotheses. A well-done integrative review meets the same standards as primary research in regard to clarity, rigor, and replication.

Structure and Writing Style

I. Thinking About Your Literature Review

The structure of a literature review should include the following :

An overview of the subject, issue or theory under consideration, along with the objectives of the literature review,
Division of works under review into themes or categories (e.g. works that support of a particular position, those against, and those offering alternative approaches entirely),
An explanation of how each work is similar to and how it varies from the others,
Conclusions as to which pieces are best considered in their argument, are most convincing of their opinions, and make the greatest contribution to the understanding and development of their area of research

The critical evaluation of each work should consider :

Provenance -- what are the author's credentials? Are the author's arguments supported by evidence (e.g. primary historical material, case studies, narratives, statistics, recent scientific findings)?
Objectivity -- is the author's perspective even-handed or prejudicial? Is contrary data considered or is certain pertinent information ignored to prove the author's point?
Persuasiveness -- which of the author's theses are most/least convincing?
Value -- are the author's arguments and conclusions convincing? Does the work ultimately contribute in any significant way to an understanding of the subject?

II. Development of the Literature Review

Four Stages

Problem formulation -- which topic or field is being examined and what are its component issues?
Literature search -- finding materials relevant to the subject being explored.
Data evaluation -- determining which literature makes a significant contribution to the understanding of the topic.
Analysis and interpretation -- discussing the findings and conclusions of pertinent literature.

Consider the following issues before writing the literature review: Clarify If your assignment is not very specific about what form your literature review should take, seek clarification from your professor by asking these questions:

Roughly how many sources should I include?
What types of sources should I review (books, journal articles, websites)?
Should I summarize, synthesize, or critique your sources by discussing a common theme or issue?
Should I evaluate the sources?
Should I provide subheadings and other background information, such as definitions and/or a history?

Find Models Use the exercise of reviewing the literature to examine how authors in your discipline or area of interest have composed their literature reviews. Read them to get a sense of the types of themes you might want to look for in your own research or ways to organize your final review. The bibliography or reference section of sources you've already read are also excellent entry points into your own research. Narrow the Topic The narrower your topic, the easier it will be to limit the number of sources you need to read in order to obtain a good survey of relevant resources. Your professor will probably not expect you to read everything that's available about the topic, but you'll make your job easier if you first limit scope of the research problem. A good strategy is to begin by searching the HOMER catalog for books about the topic and review their contents for chapters that focus on more specific issues. You can also review the subject indexes of books to find references to specific issues that can serve as the focus of your research. For example, a book surveying the history of the Israeli-Palestinian conflict may include a chapter on the role Egypt has played in mediating the conflict. Consider Whether Your Sources are Current Some disciplines require that you use information that is as current as possible. This is very common in the sciences where research conducted only two years ago could be obsolete. However, when writing a review in the social sciences, a survey of the history of the literature may be what is needed because what is important is how perspectives have changed over the years or within a certain time period. Try sorting through some other current bibliographies or literature reviews in the field to get a sense of what your discipline expects. You can also use this method to consider what is consider by scholars to be a "hot topic" and what is not.

III. Ways to Organize Your Literature Review

Chronological of Events If your review follows the chronological method, you could write about the materials according to when they were published. This approach should only be followed if a clear path of research building on previous research can be identified and that these trends follow a clear chronological order of development. For example, a literature review that focuses on continuing research about the emergence of German economic power after the fall of the Soviet Union. By Publication Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on environmental studies of brown fields if the progression revealed, for example, a change in the soil collection practices of the researchers who wrote and/or conducted the studies. Thematic (“conceptual categories”) Thematic reviews of literature are organized around a topic or issue, rather than the progression of time. However, progression of time may still be an important factor in a thematic review. For example, a review of the Internet’s impact on American presidential politics could focus on the development of online political satire. While the study focuses on one topic, the Internet’s impact on American presidential politics, it will still be organized chronologically reflecting technological developments in media. The only difference here between a "chronological" and a "thematic" approach is what is emphasized the most: the role of the Internet in presidential politics. Note however that more authentic thematic reviews tend to break away from chronological order. A review organized in this manner would shift between time periods within each section according to the point made. Methodological A methodological approach focuses on the methods utilized by the researcher. For the Internet in American presidential politics project, one methodological approach would be to look at cultural differences between the portrayal of American presidents on American, British, and French websites. Or the review might focus on the fundraising impact of the Internet on a particular political party. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed.

Other Sections of Your Literature Review Once you've decided on the organizational method for your literature review, the sections you need to include in the paper should be easy to figure out because they arise from your organizational strategy. In other words, a chronological review would have subsections for each vital time period; a thematic review would have subtopics based upon factors that relate to the theme or issue. However, sometimes you may need to add additional sections that are necessary for your study, but do not fit in the organizational strategy of the body. What other sections you include in the body is up to you but include only what is necessary for the reader to locate your study within the larger scholarship framework.

Here are examples of other sections you may need to include depending on the type of review you write:

Current Situation : information necessary to understand the topic or focus of the literature review.
History : the chronological progression of the field, the literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
Selection Methods : the criteria you used to select (and perhaps exclude) sources in your literature review. For instance, you might explain that your review includes only peer-reviewed articles and journals.
Standards : the way in which you present your information.
Questions for Further Research : What questions about the field has the review sparked? How will you further your research as a result of the review?

IV. Writing Your Literature Review

Once you've settled on how to organize your literature review, you're ready to write each section. When writing your review, keep in mind these issues.

Use Evidence A literature review in this sense is just like any other academic research paper. Your interpretation of the available sources must be backed up with evidence to show that what you are saying is valid. Be Selective Select only the most important points in each source to highlight in the review. The type of information you choose to mention should relate directly to the research problem, whether it is thematic, methodological, or chronological. Use Quotes Sparingly Some short quotes are okay if you want to emphasize a point, or if what the author said just cannot be rewritten in your own words. Sometimes you may need to quote certain terms that were coined by the author, not common knowledge, or taken directly from the study. Do not use extensive quotes as a substitute your own summary and interpretation of the literature. Summarize and Synthesize Remember to summarize and synthesize your sources within each paragraph as well as throughout the review. Recapitulate important features of a research study, but then synthesize it by rephrasing the study's significance and relating it to their own work. Keep Your Own Voice While the literature review presents others' ideas, your voice (the writer's) should remain front and center. For example, weave references to other sources into what you are writing but maintain your own voice by starting and ending the paragraph with your own ideas and wording. Use Caution When Paraphrasing When paraphrasing a source that is not your own, be sure to represent the author's information or opinions accurately and in your own words. Even when paraphrasing an author’s work, you still must provide a citation to that work.

V. Common Mistakes to Avoid

These are the most common mistakes made in reviewing social science research literature.

Sources in your literature review do not clearly relate to the research problem;
You do not take sufficient time to define and identify the most relevent sources to use in the literature review related to the research problem;
Relies exclusively on secondary analytical sources rather than including relevant primary research studies or data;
Uncritically accepts another researcher's findings and interpretations as valid, rather than examining critically all aspects of the research design and analysis;
Does not describe the search procedures that were used in the literature review;
Reports isolated statistical results rather than synthesizing them in chi-squared or meta-analytic methods; and,
Only includes research that validates assumptions and does not consider contrary findings and alternative interpretations found in the literature.

Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper. 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination. Thousand Oaks, CA: Sage Publications, 1998; Jesson, Jill. Doing Your Literature Review: Traditional and Systematic Techniques. Los Angeles, CA: London : SAGE, 2011; Literature Review Handout . Online Writing Center. Liberty University; Literature Reviews . The Writing Center. University of North Carolina; Ridley, Diana. The Literature Review: A Step-by-Step Guide for Students. 2nd ed. Los Angeles, CA: SAGE, 2012; Randolph, Justus J. “A Guide to Writing the Dissertation Literature Review." Practical Assessment, Research, and Evaluation . vol. 14, June 2009; Taylor, Dena. The Literature Review: A Few Tips On Conducting It . University College Writing Centre. University of Toronto; Writing a Literature Review. Academic Skills Centre. University of Canberra.

Writing Tip

Break Out of Your Disciplinary Box!

Thinking in an interdisciplinary way about a research problem can be a rewarding exercise in applying new ideas, theories, or concepts to an old problem. For example, what might cultural anthropologists say about the continuing conflict in the Middle East? In what ways might geographers view the need for better distribution of social service agencies in large cities than how social workers might study the issue? You don’t want to substitute a thorough review of core research literature in your discipline for studies conducted in other fields of study. However, particularly in the social sciences, thinking about research problems from multiple vectors is a key strategy for finding new solutions. Consult with a librarian about identifying research databases in other disciplines; almost every field of study has at least one comprehensive database devoted to indexing its research literature.

Another Writing Tip

Don't Just Review for Content!

How are they organizing their ideas?
What methods have they used to study the problem?
What theories have been used to explain, predict, or understand their research problem?
What sources have they cited to support of their conclusions?
How have they used non-textual elements [e.g., charts, graphs, figures, etc.] to illustrate key points?

When you begin to write your literature review section, you'll be glad you dug deeper into how the research was constructed because it lays a foundation for developing more substantial analysis and interpretation of the research problem.

Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998.

Yet Another Writing Tip

When Do I Know I Can Stop Looking and Move On?

Here are several strategies you can utilize to assess whether you've adequately reviewed the literature:

Look for repeating patterns in the research findings. If the same thing is being said, just by different people, then this likely demonstrates that the research problem has hit a conceptual dead end. At this point consider: Does your study extend current research? Does it forge a new path? Or, does is merely add more of the same thing being said?
Look at sources the authors cite to in their work. If you begin to see the same researchers cited again and again, then this is often an indication that no new ideas have been introduced in addressing the research question.
Search Google Scholar to identify who has subsequently cited leading scholars already identified in your literature review. This is called citation tracking and there are a number of sources that can help you identify who has cited whom, particularly scholars from outside of your discipline. If the same authors are being cited again and again, this may indicate no new literature has been written on the topic.
<< Previous: Theoretical Framework
Next: Citation Tracking >>
Last Updated: Jul 18, 2023 11:58 AM
URL: https://library.sacredheart.edu/c.php?g=29803
QuickSearch
Library Catalog
Databases A-Z
Publication Finder
Course Reserves
Citation Linker
Digital Commons
Our Website

Research Support

Ask a Librarian
Appointments
Interlibrary Loan (ILL)
Research Guides
Databases by Subject
Citation Help

Using the Library

Reserve a Group Study Room
Renew Books
Honors Study Rooms
Off-Campus Access
Library Policies
Library Technology

User Information

Grad Students
Online Students
COVID-19 Updates
Staff Directory
News & Announcements
Library Newsletter

My Accounts

Interlibrary Loan
Staff Site Login

FIND US ON

Help | Advanced Search

Computer Science > Human-Computer Interaction

Title: apprentices to research assistants: advancing research with large language models.

Abstract: Large Language Models (LLMs) have emerged as powerful tools in various research domains. This article examines their potential through a literature review and firsthand experimentation. While LLMs offer benefits like cost-effectiveness and efficiency, challenges such as prompt tuning, biases, and subjectivity must be addressed. The study presents insights from experiments utilizing LLMs for qualitative analysis, highlighting successes and limitations. Additionally, it discusses strategies for mitigating challenges, such as prompt optimization techniques and leveraging human expertise. This study aligns with the 'LLMs as Research Tools' workshop's focus on integrating LLMs into HCI data work critically and ethically. By addressing both opportunities and challenges, our work contributes to the ongoing dialogue on their responsible application in research.

Submission history

Access paper:.

HTML (experimental)
Other Formats

References & Citations

Google Scholar
Semantic Scholar

BibTeX formatted citation

Bibliographic and Citation Tools

Code, data and media associated with this article, recommenders and search tools.

Institution

arXivLabs: experimental projects with community collaborators

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs .

IMAGES

Sample of Research Literature Review
Sample of Research Literature Review
√ Free APA Literature Review Format Template
How to Write a Literature Review for Dissertations and Research Papers
50 Smart Literature Review Templates (APA) ᐅ TemplateLab
50 Smart Literature Review Templates (APA) ᐅ TemplateLab

VIDEO

Academic Writing Workshop
Approaches , Analysis And Sources Of Literature Review ( RESEARCH METHODOLOGY AND IPR)
Literature Review
What is a literature review?
Identifying Sources for Literature Review
Approaches to Literature Review

COMMENTS

How to Write a Literature Review
Examples of literature reviews. Step 1 - Search for relevant literature. Step 2 - Evaluate and select sources. Step 3 - Identify themes, debates, and gaps. Step 4 - Outline your literature review's structure. Step 5 - Write your literature review.
Writing a Literature Review
A literature review can be a part of a research paper or scholarly article, usually falling after the introduction and before the research methods sections. In these cases, the lit review just needs to cover scholarship that is important to the issue you are writing about; sometimes it will also cover key sources that informed your research ...
What is a Literature Review? How to Write It (with Examples)
A literature review is a critical analysis and synthesis of existing research on a particular topic. It provides an overview of the current state of knowledge, identifies gaps, and highlights key findings in the literature. 1 The purpose of a literature review is to situate your own research within the context of existing scholarship ...
Writing a Literature Review Research Paper: A step-by-step approach
A literature review is a surveys scholarly articles, books and other sources relevant to a particular. issue, area of research, or theory, and by so doing, providing a description, summary, and ...
How to write the literature review of your research paper
The main purpose of the review is to introduce the readers to the need for conducting the said research. A literature review should begin with a thorough literature search using the main keywords in relevant online databases such as Google Scholar, PubMed, etc. Once all the relevant literature has been gathered, it should be organized as ...
What is a literature review?
A literature or narrative review is a comprehensive review and analysis of the published literature on a specific topic or research question. The literature that is reviewed contains: books, articles, academic articles, conference proceedings, association papers, and dissertations. It contains the most pertinent studies and points to important ...
What is a Literature Review?
A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research. There are five key steps to writing a literature review: Search for relevant literature. Evaluate sources. Identify themes, debates and gaps.
Writing a literature review
Writing a literature review requires a range of skills to gather, sort, evaluate and summarise peer-reviewed published data into a relevant and informative unbiased narrative. Digital access to research papers, academic texts, review articles, reference databases and public data sets are all sources of information that are available to enrich ...
What is a literature review? [with examples]
Definition. A literature review is an assessment of the sources in a chosen topic of research. In a literature review, you're expected to report on the existing scholarly conversation, without adding new contributions. If you are currently writing one, you've come to the right place. In the following paragraphs, we will explain: the objective ...
How to write a superb literature review
One of my favourite review-style articles 3 presents a plot bringing together data from multiple research papers (many of which directly contradict each other). This is then used to identify broad ...
Research Guides: Literature Reviews: What is a Literature Review?
A literature review is a review and synthesis of existing research on a topic or research question. A literature review is meant to analyze the scholarly literature, make connections across writings and identify strengths, weaknesses, trends, and missing conversations. A literature review should address different aspects of a topic as it ...
Literature Review: The What, Why and How-to Guide
In writing the literature review, your purpose is to convey to your reader what knowledge and ideas have been established on a topic, and what their strengths and weaknesses are. As a piece of writing, the literature review must be defined by a guiding concept (e.g., your research objective, the problem or issue you are discussing, or your ...
Steps in Conducting a Literature Review
A literature review is an integrated analysis-- not just a summary-- of scholarly writings and other relevant evidence related directly to your research question.That is, it represents a synthesis of the evidence that provides background information on your topic and shows a association between the evidence and your research question.
How To Write A Literature Review (+ Free Template)
Quality research is about building onto the existing work of others, "standing on the shoulders of giants", as Newton put it.The literature review chapter of your dissertation, thesis or research project is where you synthesise this prior work and lay the theoretical foundation for your own research.. Long story short, this chapter is a pretty big deal, which is why you want to make sure ...
5. The Literature Review
A literature review may consist of simply a summary of key sources, but in the social sciences, a literature review usually has an organizational pattern and combines both summary and synthesis, often within specific conceptual categories.A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information in a way that ...
Literature Reviews
In a research paper, you use the literature as a foundation and as support for a new insight that you contribute. The focus of a literature review, however, is to summarize and synthesize the arguments and ideas of others without adding new contributions. ... A literature review, like a term paper, is usually organized around ideas, not the ...
Ten Simple Rules for Writing a Literature Review
Literature reviews are in great demand in most scientific fields. Their need stems from the ever-increasing output of scientific publications .For example, compared to 1991, in 2008 three, eight, and forty times more papers were indexed in Web of Science on malaria, obesity, and biodiversity, respectively .Given such mountains of papers, scientists cannot be expected to examine in detail every ...
Guidance on Conducting a Systematic Literature Review
This article is organized as follows: The next section presents the methodology adopted by this research, followed by a section that discusses the typology of literature reviews and provides empirical examples; the subsequent section summarizes the process of literature review; and the last section concludes the paper with suggestions on how to improve the quality and rigor of literature ...
Literature Review: Conducting & Writing
Steps for Conducting a Lit Review; Finding "The Literature" Organizing/Writing; APA Style This link opens in a new window; Chicago: Notes Bibliography This link opens in a new window; MLA Style This link opens in a new window; Sample Literature Reviews. Sample Lit Reviews from Communication Arts; Have an exemplary literature review? Get Help!
Literature review as a research methodology: An overview and guidelines
This paper discusses literature review as a methodology for conducting research and offers an overview of different types of reviews, as well as some guidelines to how to both conduct and evaluate a literature review paper. It also discusses common pitfalls and how to get literature reviews published. 1.
Literature Review Research
Literature Review is a comprehensive survey of the works published in a particular field of study or line of research, usually over a specific period of time, in the form of an in-depth, critical bibliographic essay or annotated list in which attention is drawn to the most significant works.. Also, we can define a literature review as the collected body of scholarly works related to a topic:
Approaching literature review for academic purposes: The Literature
Therefore, this paper discusses the purposes of LRs in dissertations and theses. Second, the paper considers five steps for developing a review: defining the main topic, searching the literature, analyzing the results, writing the review and reflecting on the writing. Ultimately, this study proposes a twelve-item LR checklist.
Create a Literature Review
For scholars, the depth and breadth of the literature review emphasizes the credibility of the writer in his or her field. Literature reviews also provide a solid background for a research paper's investigation. Comprehensive knowledge of the literature of the field is essential to most research papers.
Toward a framework for selecting indicators of measuring ...
4.1 Review methodology. A systematic literature review approach (SLR) was used to answer the research questions. The aim of SLR is "to identify, evaluate, and interpret research relevant to a determined topic area, research question, or phenomenon of interest" (Kitchenham and Charters 2007; Muller et al. 2019, p. 398).
Literature review of stroke assessment for upper-extremity physical
In step 2, resulting titles and abstracts were screened to remove duplicates, articles in other languages, and articles not related to the literature review. In step 3, researchers read the full texts of articles screened in step 2, papers qualifying for inclusion using the Literature Review Criteria in Table 1 were selected. Finally, in step 4 ...
PDF Nber Working Paper Series Working From Home, Worker Sorting and Development
views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been ... 1.1 Related Literature This paper contributes to several literatures in economics. First, we are motivated by the literature that ... The Role of Allocation and Selection," American Economic Review ...
Dynamic capabilities view practices of business firms: a systematic
This systematic literature review identified relevant research articles, allowing for a transparent, documented research process with inclusion and exclusion criteria. ... Emerald insight was used to publish the majority of academics' research papers (9 of 42 publications from the 42 research databases were chosen as a finding). The second ...
Climate Shocks and the Poor: A Review of the Literature
There is a rapidly growing literature on the link between climate change and poverty. This study reviews the existing literature on whether the poor are more exposed to climate shocks and whether they are more adversely affected.
Organizing Academic Research Papers: 5. The Literature Review
A literature review may consist of simple a summary of key sources, but it usually has an organizational pattern and combines both summary and synthesis, often within specific conceptual categories.A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information in a way that informs how you are planning to investigate ...
Apprentices to Research Assistants: Advancing Research with Large
Large Language Models (LLMs) have emerged as powerful tools in various research domains. This article examines their potential through a literature review and firsthand experimentation. While LLMs offer benefits like cost-effectiveness and efficiency, challenges such as prompt tuning, biases, and subjectivity must be addressed. The study presents insights from experiments utilizing LLMs for ...

Have a language expert improve your writing

How to Write a Literature Review | Guide, Examples, & Templates

Instantly correct all language mistakes in your text

Table of contents

Here's why students love Scribbr's proofreading services

Make a list of keywords

Search for relevant sources

Take notes and cite your sources

The only proofreading tool specialized in correcting academic writing - try for free!

Chronological

Methodological

Theoretical

Cite this Scribbr article

Is this article helpful?

Shona McCombes

Writing a Literature Review

Welcome to the Purdue OWL

Where, when, and why would I write a lit review?

What are the parts of a lit review?

How should I organize my lit review?

What are some strategies or tips I can use while writing my lit review?

What is a Literature Review? How to Write It (with Examples)

Table of Contents

What is a literature review?

What is the purpose of literature review?

Literature review example

Literature Review on Climate Change Impacts on Biodiversity:

a. Habitat Loss and Species Extinction:

b. Range Shifts and Phenological Changes:

c. Ocean Acidification and Coral Reefs:

d. Adaptive Strategies and Conservation Efforts:

How to write a good literature review

Conducting a literature review

Choose a Topic and Define the Research Question:

Decide on the Scope of Your Review:

Select Databases for Searches:

Conduct Searches and Keep Track:

Review the Literature:

Organize and Write Your Literature Review:

Frequently asked questions

Related Reads:

6 Tips for Post-Doc Researchers to Take Their Career to the Next Level

Literature Reviews

What is a Literature Review?

Purpose of a Literature Review

Limitations of a Literature Review

Have a language expert improve your writing

What is a Literature Review? | Guide, Template, & Examples

Instantly correct all language mistakes in your text

Table of contents

The only proofreading tool specialized in correcting academic writing

Make a list of keywords

Search for relevant sources

Take notes and cite your sources

Chronological

Methodological

Theoretical

Cite this Scribbr article

Is this article helpful?

Shona McCombes

What is a literature review? [with examples]

What is a literature review?

How to write a superb literature review

Access options

Updates & Corrections

Related Articles

Junior Group Leader Position at IMBA - Institute of Molecular Biotechnology

Open Rank Faculty, Center for Public Health Genomics

Husbandry Technician I

Lead Researcher – Department of Bone Marrow Transplantation & Cellular Therapy

Quick links

Libraries | Research Guides

Literature Review: The What, Why and How-to Guide — Introduction

What are Literature Reviews?

Goals of Literature Reviews

Types of Literature Reviews

Literature Reviews in the Health Sciences

Harvey Cushing/John Hay Whitney Medical Library

YSN Doctoral Programs: Steps in Conducting a Literature Review

What is a literature review?