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Types of Research – Explained with Examples
- By DiscoverPhDs
- October 2, 2020
Types of Research
Research is about using established methods to investigate a problem or question in detail with the aim of generating new knowledge about it.
It is a vital tool for scientific advancement because it allows researchers to prove or refute hypotheses based on clearly defined parameters, environments and assumptions. Due to this, it enables us to confidently contribute to knowledge as it allows research to be verified and replicated.
Knowing the types of research and what each of them focuses on will allow you to better plan your project, utilises the most appropriate methodologies and techniques and better communicate your findings to other researchers and supervisors.
Classification of Types of Research
There are various types of research that are classified according to their objective, depth of study, analysed data, time required to study the phenomenon and other factors. It’s important to note that a research project will not be limited to one type of research, but will likely use several.
According to its Purpose
Theoretical research.
Theoretical research, also referred to as pure or basic research, focuses on generating knowledge , regardless of its practical application. Here, data collection is used to generate new general concepts for a better understanding of a particular field or to answer a theoretical research question.
Results of this kind are usually oriented towards the formulation of theories and are usually based on documentary analysis, the development of mathematical formulas and the reflection of high-level researchers.
Applied Research
Here, the goal is to find strategies that can be used to address a specific research problem. Applied research draws on theory to generate practical scientific knowledge, and its use is very common in STEM fields such as engineering, computer science and medicine.
This type of research is subdivided into two types:
- Technological applied research : looks towards improving efficiency in a particular productive sector through the improvement of processes or machinery related to said productive processes.
- Scientific applied research : has predictive purposes. Through this type of research design, we can measure certain variables to predict behaviours useful to the goods and services sector, such as consumption patterns and viability of commercial projects.
According to your Depth of Scope
Exploratory research.
Exploratory research is used for the preliminary investigation of a subject that is not yet well understood or sufficiently researched. It serves to establish a frame of reference and a hypothesis from which an in-depth study can be developed that will enable conclusive results to be generated.
Because exploratory research is based on the study of little-studied phenomena, it relies less on theory and more on the collection of data to identify patterns that explain these phenomena.
Descriptive Research
The primary objective of descriptive research is to define the characteristics of a particular phenomenon without necessarily investigating the causes that produce it.
In this type of research, the researcher must take particular care not to intervene in the observed object or phenomenon, as its behaviour may change if an external factor is involved.
Explanatory Research
Explanatory research is the most common type of research method and is responsible for establishing cause-and-effect relationships that allow generalisations to be extended to similar realities. It is closely related to descriptive research, although it provides additional information about the observed object and its interactions with the environment.
Correlational Research
The purpose of this type of scientific research is to identify the relationship between two or more variables. A correlational study aims to determine whether a variable changes, how much the other elements of the observed system change.
According to the Type of Data Used
Qualitative research.
Qualitative methods are often used in the social sciences to collect, compare and interpret information, has a linguistic-semiotic basis and is used in techniques such as discourse analysis, interviews, surveys, records and participant observations.
In order to use statistical methods to validate their results, the observations collected must be evaluated numerically. Qualitative research, however, tends to be subjective, since not all data can be fully controlled. Therefore, this type of research design is better suited to extracting meaning from an event or phenomenon (the ‘why’) than its cause (the ‘how’).
Quantitative Research
Quantitative research study delves into a phenomena through quantitative data collection and using mathematical, statistical and computer-aided tools to measure them . This allows generalised conclusions to be projected over time.
According to the Degree of Manipulation of Variables
Experimental research.
It is about designing or replicating a phenomenon whose variables are manipulated under strictly controlled conditions in order to identify or discover its effect on another independent variable or object. The phenomenon to be studied is measured through study and control groups, and according to the guidelines of the scientific method.
Non-Experimental Research
Also known as an observational study, it focuses on the analysis of a phenomenon in its natural context. As such, the researcher does not intervene directly, but limits their involvement to measuring the variables required for the study. Due to its observational nature, it is often used in descriptive research.
Quasi-Experimental Research
It controls only some variables of the phenomenon under investigation and is therefore not entirely experimental. In this case, the study and the focus group cannot be randomly selected, but are chosen from existing groups or populations . This is to ensure the collected data is relevant and that the knowledge, perspectives and opinions of the population can be incorporated into the study.
According to the Type of Inference
Deductive investigation.
In this type of research, reality is explained by general laws that point to certain conclusions; conclusions are expected to be part of the premise of the research problem and considered correct if the premise is valid and the inductive method is applied correctly.
Inductive Research
In this type of research, knowledge is generated from an observation to achieve a generalisation. It is based on the collection of specific data to develop new theories.
Hypothetical-Deductive Investigation
It is based on observing reality to make a hypothesis, then use deduction to obtain a conclusion and finally verify or reject it through experience.
According to the Time in Which it is Carried Out
Longitudinal study (also referred to as diachronic research).
It is the monitoring of the same event, individual or group over a defined period of time. It aims to track changes in a number of variables and see how they evolve over time. It is often used in medical, psychological and social areas .
Cross-Sectional Study (also referred to as Synchronous Research)
Cross-sectional research design is used to observe phenomena, an individual or a group of research subjects at a given time.
According to The Sources of Information
Primary research.
This fundamental research type is defined by the fact that the data is collected directly from the source, that is, it consists of primary, first-hand information.
Secondary research
Unlike primary research, secondary research is developed with information from secondary sources, which are generally based on scientific literature and other documents compiled by another researcher.
According to How the Data is Obtained
Documentary (cabinet).
Documentary research, or secondary sources, is based on a systematic review of existing sources of information on a particular subject. This type of scientific research is commonly used when undertaking literature reviews or producing a case study.
Field research study involves the direct collection of information at the location where the observed phenomenon occurs.
From Laboratory
Laboratory research is carried out in a controlled environment in order to isolate a dependent variable and establish its relationship with other variables through scientific methods.
Mixed-Method: Documentary, Field and/or Laboratory
Mixed research methodologies combine results from both secondary (documentary) sources and primary sources through field or laboratory research.
In the UK, a dissertation, usually around 20,000 words is written by undergraduate and Master’s students, whilst a thesis, around 80,000 words, is written as part of a PhD.
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Study designs
This short article gives a brief guide to the different study types and a comparison of the advantages and disadvantages.
See also Levels of Evidence
These study designs all have similar components (as we’d expect from the PICO):
- A defined population (P) from which groups of subjects are studied
- Outcomes (O) that are measured
And for experimental and analytic observational studies:
- Interventions (I) or exposures (E) that are applied to different groups of subjects
Overview of the design tree
Figure 1 shows the tree of possible designs, branching into subgroups of study designs by whether the studies are descriptive or analytic and by whether the analytic studies are experimental or observational. The list is not completely exhaustive but covers most basics designs.
Figure: Tree of different types of studies (Q1, 2, and 3 refer to the three questions below)
> Download a PDF by Jeremy Howick about study designs
Our first distinction is whether the study is analytic or non-analytic. A non-analytic or descriptive study does not try to quantify the relationship but tries to give us a picture of what is happening in a population, e.g., the prevalence, incidence, or experience of a group. Descriptive studies include case reports, case-series, qualitative studies and surveys (cross-sectional) studies, which measure the frequency of several factors, and hence the size of the problem. They may sometimes also include analytic work (comparing factors “” see below).
An analytic study attempts to quantify the relationship between two factors, that is, the effect of an intervention (I) or exposure (E) on an outcome (O). To quantify the effect we will need to know the rate of outcomes in a comparison (C) group as well as the intervention or exposed group. Whether the researcher actively changes a factor or imposes uses an intervention determines whether the study is considered to be observational (passive involvement of researcher), or experimental (active involvement of researcher).
In experimental studies, the researcher manipulates the exposure, that is he or she allocates subjects to the intervention or exposure group. Experimental studies, or randomised controlled trials (RCTs), are similar to experiments in other areas of science. That is, subjects are allocated to two or more groups to receive an intervention or exposure and then followed up under carefully controlled conditions. Such studies controlled trials, particularly if randomised and blinded, have the potential to control for most of the biases that can occur in scientific studies but whether this actually occurs depends on the quality of the study design and implementation.
In analytic observational studies, the researcher simply measures the exposure or treatments of the groups. Analytical observational studies include case””control studies, cohort studies and some population (cross-sectional) studies. These studies all include matched groups of subjects and assess of associations between exposures and outcomes.
Observational studies investigate and record exposures (such as interventions or risk factors) and observe outcomes (such as disease) as they occur. Such studies may be purely descriptive or more analytical.
We should finally note that studies can incorporate several design elements. For example, a the control arm of a randomised trial may also be used as a cohort study; and the baseline measures of a cohort study may be used as a cross-sectional study.
Spotting the study design
The type of study can generally be worked at by looking at three issues (as per the Tree of design in Figure 1):
Q1. What was the aim of the study?
- To simply describe a population (PO questions) descriptive
- To quantify the relationship between factors (PICO questions) analytic.
Q2. If analytic, was the intervention randomly allocated?
- No? Observational study
For observational study the main types will then depend on the timing of the measurement of outcome, so our third question is:
Q3. When were the outcomes determined?
- Some time after the exposure or intervention? cohort study (‘prospective study’)
- At the same time as the exposure or intervention? cross sectional study or survey
- Before the exposure was determined? case-control study (‘retrospective study’ based on recall of the exposure)
Advantages and Disadvantages of the Designs
Randomised Controlled Trial
An experimental comparison study in which participants are allocated to treatment/intervention or control/placebo groups using a random mechanism (see randomisation). Best for study the effect of an intervention.
Advantages:
- unbiased distribution of confounders;
- blinding more likely;
- randomisation facilitates statistical analysis.
Disadvantages:
- expensive: time and money;
- volunteer bias;
- ethically problematic at times.
Crossover Design
A controlled trial where each study participant has both therapies, e.g, is randomised to treatment A first, at the crossover point they then start treatment B. Only relevant if the outcome is reversible with time, e.g, symptoms.
- all subjects serve as own controls and error variance is reduced thus reducing sample size needed;
- all subjects receive treatment (at least some of the time);
- statistical tests assuming randomisation can be used;
- blinding can be maintained.
- all subjects receive placebo or alternative treatment at some point;
- washout period lengthy or unknown;
- cannot be used for treatments with permanent effects
Cohort Study
Data are obtained from groups who have been exposed, or not exposed, to the new technology or factor of interest (eg from databases). No allocation of exposure is made by the researcher. Best for study the effect of predictive risk factors on an outcome.
- ethically safe;
- subjects can be matched;
- can establish timing and directionality of events;
- eligibility criteria and outcome assessments can be standardised;
- administratively easier and cheaper than RCT.
- controls may be difficult to identify;
- exposure may be linked to a hidden confounder;
- blinding is difficult;
- randomisation not present;
- for rare disease, large sample sizes or long follow-up necessary.
Case-Control Studies
Patients with a certain outcome or disease and an appropriate group of controls without the outcome or disease are selected (usually with careful consideration of appropriate choice of controls, matching, etc) and then information is obtained on whether the subjects have been exposed to the factor under investigation.
- quick and cheap;
- only feasible method for very rare disorders or those with long lag between exposure and outcome;
- fewer subjects needed than cross-sectional studies.
- reliance on recall or records to determine exposure status;
- confounders;
- selection of control groups is difficult;
- potential bias: recall, selection.
Cross-Sectional Survey
A study that examines the relationship between diseases (or other health-related characteristics) and other variables of interest as they exist in a defined population at one particular time (ie exposure and outcomes are both measured at the same time). Best for quantifying the prevalence of a disease or risk factor, and for quantifying the accuracy of a diagnostic test.
- cheap and simple;
- ethically safe.
- establishes association at most, not causality;
- recall bias susceptibility;
- confounders may be unequally distributed;
- Neyman bias;
- group sizes may be unequal.
Ultimate Guide to the 7 Types of Research: Definitions, Examples, Advantages and Limitations!
About the article : different types of research.
Research is a fundamental aspect of any field of study, providing a systematic approach to gather and analyze information. It plays a crucial role in expanding knowledge, solving problems, and making informed decisions. Understanding the different types of research is essential for researchers to choose the most appropriate method for their study.
In this article, we will explore the various types of research methods commonly used in academic and professional settings. Each type of research has its own unique characteristics, strengths, and limitations. By gaining a comprehensive understanding of these research types, researchers can effectively design and conduct their studies to achieve their objectives.
Exploratory Research
Exploratory research is a type of research that is used to investigate a problem that is not clearly defined and gain a better understanding of the existing problem. It is often conducted when a researcher has just begun an investigation and wishes to understand the topic generally.
There are two main methods of conducting exploratory research: primary research and secondary research. Primary research involves collecting new data directly from the source, while secondary research involves analyzing existing data that has already been collected by others.
Under these two broad types, various methods can be employed to gather information. These methods include surveys, interviews , focus groups, observations, and case studies. Each method has its own advantages and disadvantages, and the choice of method depends on the nature of the research question and the available resources.
Exploratory research is valuable because it helps researchers gain insights and generate hypotheses for further investigation. It allows them to explore new areas of study and discover potential relationships between variables. However, it is important to note that exploratory research does not provide definitive answers or conclusive results. Instead, it lays the foundation for more in-depth research and helps researchers refine their research questions and methodologies.
Descriptive Research
Descriptive research is a methodological approach that seeks to depict the characteristics of a phenomenon or subject under investigation. It involves observing and measuring without manipulating variables, allowing researchers to identify characteristics, trends, and correlations. The main goal of descriptive research is to provide a detailed description of the population or phenomenon being studied. This type of research focuses on answering questions such as how, what, when, and where.
There are three basic approaches for gathering data in descriptive research: observational, case study, and survey. Observational research involves observing and recording behavior in its natural setting. Case study research involves in-depth analysis of a single individual, group, or situation. Survey research involves collecting data from a sample of individuals through questionnaires or interviews.
Descriptive research is particularly useful when researchers want to describe specific behaviors, characteristics, or trends as they occur in the environment. It provides a foundation for further research and can help generate hypotheses for future studies.
However, one limitation of descriptive research is that it does not establish causal relationships between variables. It can only provide a snapshot of the current state of the population or phenomenon being studied. Despite this limitation, descriptive research plays a crucial role in understanding and describing various aspects of the world around us.
Experimental Research
Experimental research is a quantitative research method with a scientific approach. It is the most familiar type of research design for individuals in the physical sciences and a host of other fields. This type of research design is popular in scientific experiments, social sciences, medical science, etc. Experimental research involves manipulating one or more variables to observe the effect on another variable. It aims to establish cause-and-effect relationships between variables. The researcher carefully controls and manipulates the independent variable(s) while measuring the dependent variable(s).
There are two broad categories of experimental research designs: true experimental designs and quasi-experimental designs. True experimental designs involve random assignment of participants to different groups and manipulation of the independent variable. Quasi-experimental designs lack random assignment but still involve manipulation of the independent variable.
One advantage of experimental research is its ability to establish causal relationships. By manipulating variables and controlling extraneous factors, researchers can determine whether changes in the independent variable(s) cause changes in the dependent variable(s). This allows for a more confident understanding of cause and effect.
Another advantage of experimental research is its versatility. It can be used in various fields and disciplines, allowing researchers to investigate a wide range of phenomena. Whether it’s testing the effectiveness of a new drug, studying the impact of different teaching methods, or exploring the relationship between variables, experimental research provides a powerful tool for scientific inquiry.
However, experimental research also has some limitations. One limitation is the potential for artificiality. In a controlled laboratory setting, variables may be manipulated in a way that does not fully reflect real-world conditions. This can limit the generalizability of the findings to real-life situations. Additionally, experimental research may face ethical considerations. Manipulating variables and potentially exposing participants to certain conditions can raise ethical concerns. Researchers must ensure that the benefits of the study outweigh any potential risks or harm to participants.
Correlational Research
Correlational research is a type of non-experimental research that focuses on observing and measuring the relationship between two or more variables. Unlike experimental research, the researcher does not control or manipulate the variables in correlational research. The main purpose of correlational research is to determine if there is a statistical relationship between the variables being studied. It involves comparing two variables and data sources, assessing the relationship between them, and identifying any trends or patterns.
There are several types of correlational studies that can be conducted. One type is positive correlation, which occurs when an increase in one variable is associated with an increase in another variable. For example, there may be a positive correlation between income and education level, meaning that as income increases, education level also tends to increase.
On the other hand, negative correlation refers to a relationship where an increase in one variable is associated with a decrease in another variable. An example of negative correlation could be the relationship between hours spent studying and test scores. As the number of hours spent studying increases, test scores tend to decrease. Lastly, zero correlation indicates that there is no relationship between the variables being studied. This means that changes in one variable do not affect the other variable. For instance, there may be zero correlation between shoe size and intelligence.
Correlational research is commonly used in various fields, including psychology, sociology, and marketing. It provides valuable insights into the relationships between variables and helps researchers understand the patterns and trends in data. However, correlational research has its limitations. Since it does not involve manipulation of variables, it cannot establish causation. It can only identify associations between variables. Additionally, correlational research relies on the accuracy and reliability of the data collected, which can be influenced by various factors.
Causal-Comparative Research
Causal-comparative research is a methodology used to identify cause-effect relationships between independent and dependent variables. It is a type of research method where the researcher tries to find out if there is a causal effect relationship between two or more groups or variables.
The main objective of causal-comparative research is to determine the cause or reason for pre-existing differences in groups of individuals. This research design involves comparing groups that have already been formed based on a specific characteristic or condition. The researcher then analyzes the differences between these groups to identify any causal relationships.
There are two types of causal-comparative research designs: retrospective and prospective. Retrospective causal-comparative research looks at past events or conditions to determine the cause-effect relationship. On the other hand, prospective causal-comparative research looks at current or future events or conditions to identify the causal relationship.
One example of causal-comparative research is a study comparing the critical thinking skills of students who were taught using the inquiry method versus those who were taught using the lecture method. The researcher would compare the two groups of students and analyze the differences in their critical thinking abilities to determine if the teaching method had a causal effect on their skills.
Causal-comparative research has its advantages and disadvantages. One advantage is that it allows researchers to study cause-effect relationships in situations where it is not possible or ethical to manipulate variables. It also provides valuable insights into the factors that contribute to differences between groups.
However, a limitation of causal-comparative research is that it cannot establish a cause-effect relationship with certainty, as there may be other variables or factors that influence the observed differences between groups.
Qualitative Research
Qualitative research is a type of research that explores and provides deeper insights into real-world problems. Instead of collecting numerical data, qualitative research deals with data types such as text, audio, images, and video, focusing on the variety of human experiences and perspectives.
There are different types of qualitative research methods that researchers can use depending on their study requirements. Some common qualitative research methods include in-depth interviews, focus groups, ethnographic research, content analysis, and case study. In-depth interviews involve conducting one-on-one interviews with participants to gather detailed information about their experiences, opinions, and perspectives. This method allows researchers to delve deep into the thoughts and feelings of individuals and gain a comprehensive understanding of their experiences.
Focus groups involve bringing together a small group of participants to discuss a specific topic or issue. The group dynamic allows for the exploration of different perspectives and the generation of rich and diverse insights. Focus groups are particularly useful for understanding social interactions and group dynamics. Ethnographic research involves immersing the researcher in the natural environment of the participants to observe and understand their behaviors, beliefs, and cultural practices. This method allows for a holistic understanding of the social and cultural context in which individuals operate.
Content analysis involves systematically analyzing textual, audio, or visual data to identify patterns, themes, and meanings. This method is often used to analyze documents, media content, or online discussions to gain insights into societal trends, attitudes, or representations. Case study research involves in-depth investigation of a specific individual, group, or organization. Researchers collect and analyze multiple sources of data to gain a comprehensive understanding of the case under study. Case studies are particularly useful for exploring complex phenomena or unique situations.
Qualitative research provides several advantages. It allows researchers to explore complex and nuanced phenomena in depth, providing rich and detailed insights. It also allows for flexibility and adaptability in the research process, as researchers can adjust their approach based on emerging findings. Additionally, qualitative research is often used to generate hypotheses or theories that can be further tested using quantitative research methods.
However, qualitative research also has some limitations. The findings are often context-specific and may not be generalizable to a larger population. The subjective nature of qualitative data collection and analysis can introduce bias and interpretation challenges. Qualitative research also requires significant time and resources, as data collection and analysis can be time-consuming and labor-intensive.
Quantitative Research
Quantitative research is a type of research that involves collecting and analyzing numerical data to describe characteristics, find correlations, or test hypotheses. It is characterized by structured tools like surveys, substantial sample sizes, closed-ended questions, and reliance on prior studies.
There are two main types of quantitative research: primary and secondary. Primary quantitative research involves collecting data directly from the source, such as through surveys or experiments. Secondary quantitative research, on the other hand, involves analyzing existing data that has been collected by someone else.
Quantitative research methods can be used to quantify opinions, behaviors, attitudes, and other definitive variables related to the market, customers, competitors, and more. It provides a systematic and objective approach to studying phenomena and allows for statistical analysis to draw conclusions.
There are several types of quantitative research designs that can be used, depending on the research objectives . These include descriptive research, correlational research, causal-comparative research, and experimental research as per explained above.
In conclusion, understanding the different types of research is essential for conducting effective and meaningful studies. Each type of research has its own strengths and limitations, and researchers must carefully consider which approach is the most appropriate for their specific research question and objectives. It is important to recognize that research is an iterative process, and different types of research may be used at different stages of a study.
In summary, the various types of research offer different perspectives and methodologies for investigating and understanding the world around us. By utilizing a combination of these approaches, researchers can gain a comprehensive understanding of complex phenomena and make meaningful contributions to their fields of study.
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An introduction to different types of study design
Posted on 6th April 2021 by Hadi Abbas
Study designs are the set of methods and procedures used to collect and analyze data in a study.
Broadly speaking, there are 2 types of study designs: descriptive studies and analytical studies.
Descriptive studies
- Describes specific characteristics in a population of interest
- The most common forms are case reports and case series
- In a case report, we discuss our experience with the patient’s symptoms, signs, diagnosis, and treatment
- In a case series, several patients with similar experiences are grouped.
Analytical Studies
Analytical studies are of 2 types: observational and experimental.
Observational studies are studies that we conduct without any intervention or experiment. In those studies, we purely observe the outcomes. On the other hand, in experimental studies, we conduct experiments and interventions.
Observational studies
Observational studies include many subtypes. Below, I will discuss the most common designs.
Cross-sectional study:
- This design is transverse where we take a specific sample at a specific time without any follow-up
- It allows us to calculate the frequency of disease ( p revalence ) or the frequency of a risk factor
- This design is easy to conduct
- For example – if we want to know the prevalence of migraine in a population, we can conduct a cross-sectional study whereby we take a sample from the population and calculate the number of patients with migraine headaches.
Cohort study:
- We conduct this study by comparing two samples from the population: one sample with a risk factor while the other lacks this risk factor
- It shows us the risk of developing the disease in individuals with the risk factor compared to those without the risk factor ( RR = relative risk )
- Prospective : we follow the individuals in the future to know who will develop the disease
- Retrospective : we look to the past to know who developed the disease (e.g. using medical records)
- This design is the strongest among the observational studies
- For example – to find out the relative risk of developing chronic obstructive pulmonary disease (COPD) among smokers, we take a sample including smokers and non-smokers. Then, we calculate the number of individuals with COPD among both.
Case-Control Study:
- We conduct this study by comparing 2 groups: one group with the disease (cases) and another group without the disease (controls)
- This design is always retrospective
- We aim to find out the odds of having a risk factor or an exposure if an individual has a specific disease (Odds ratio)
- Relatively easy to conduct
- For example – we want to study the odds of being a smoker among hypertensive patients compared to normotensive ones. To do so, we choose a group of patients diagnosed with hypertension and another group that serves as the control (normal blood pressure). Then we study their smoking history to find out if there is a correlation.
Experimental Studies
- Also known as interventional studies
- Can involve animals and humans
- Pre-clinical trials involve animals
- Clinical trials are experimental studies involving humans
- In clinical trials, we study the effect of an intervention compared to another intervention or placebo. As an example, I have listed the four phases of a drug trial:
I: We aim to assess the safety of the drug ( is it safe ? )
II: We aim to assess the efficacy of the drug ( does it work ? )
III: We want to know if this drug is better than the old treatment ( is it better ? )
IV: We follow-up to detect long-term side effects ( can it stay in the market ? )
- In randomized controlled trials, one group of participants receives the control, while the other receives the tested drug/intervention. Those studies are the best way to evaluate the efficacy of a treatment.
Finally, the figure below will help you with your understanding of different types of study designs.
References (pdf)
You may also be interested in the following blogs for further reading:
An introduction to randomized controlled trials
Case-control and cohort studies: a brief overview
Cohort studies: prospective and retrospective designs
Prevalence vs Incidence: what is the difference?
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No Comments on An introduction to different types of study design
you are amazing one!! if I get you I’m working with you! I’m student from Ethiopian higher education. health sciences student
Very informative and easy understandable
You are my kind of doctor. Do not lose sight of your objective.
Wow very erll explained and easy to understand
I’m Khamisu Habibu community health officer student from Abubakar Tafawa Balewa university teaching hospital Bauchi, Nigeria, I really appreciate your write up and you have make it clear for the learner. thank you
well understood,thank you so much
Well understood…thanks
Simply explained. Thank You.
Thanks a lot for this nice informative article which help me to understand different study designs that I felt difficult before
That’s lovely to hear, Mona, thank you for letting the author know how useful this was. If there are any other particular topics you think would be useful to you, and are not already on the website, please do let us know.
it is very informative and useful.
thank you statistician
Fabulous to hear, thank you John.
Thanks for this information
Thanks so much for this information….I have clearly known the types of study design Thanks
That’s so good to hear, Mirembe, thank you for letting the author know.
Very helpful article!! U have simplified everything for easy understanding
I’m a health science major currently taking statistics for health care workers…this is a challenging class…thanks for the simified feedback.
That’s good to hear this has helped you. Hopefully you will find some of the other blogs useful too. If you see any topics that are missing from the website, please do let us know!
Hello. I liked your presentation, the fact that you ranked them clearly is very helpful to understand for people like me who is a novelist researcher. However, I was expecting to read much more about the Experimental studies. So please direct me if you already have or will one day. Thank you
Dear Ay. My sincere apologies for not responding to your comment sooner. You may find it useful to filter the blogs by the topic of ‘Study design and research methods’ – here is a link to that filter: https://s4be.cochrane.org/blog/topic/study-design/ This will cover more detail about experimental studies. Or have a look on our library page for further resources there – you’ll find that on the ‘Resources’ drop down from the home page.
However, if there are specific things you feel you would like to learn about experimental studies, that are missing from the website, it would be great if you could let me know too. Thank you, and best of luck. Emma
Great job Mr Hadi. I advise you to prepare and study for the Australian Medical Board Exams as soon as you finish your undergrad study in Lebanon. Good luck and hope we can meet sometime in the future. Regards ;)
You have give a good explaination of what am looking for. However, references am not sure of where to get them from.
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Cluster Randomized Trials: Concepts
This blog summarizes the concepts of cluster randomization, and the logistical and statistical considerations while designing a cluster randomized controlled trial.
Expertise-based Randomized Controlled Trials
This blog summarizes the concepts of Expertise-based randomized controlled trials with a focus on the advantages and challenges associated with this type of study.
A well-designed cohort study can provide powerful results. This blog introduces prospective and retrospective cohort studies, discussing the advantages, disadvantages and use of these type of study designs.
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