Case Study – Guide with Definition, Types & Examples

Time to read: 5 Minutes

Case studies are used in different types of research for describing, evaluating and comparing different variables in a research problem. A well-formulated case study guides the process and methodology of research.1

Case Study – In a Nutshell

  • Case studies can capture several perspectives or a single focus, depending on the scope of the study.
  • Researchers use case studies as a standalone approach or as part of a more extensive study.
  • Case studies contribute to the body of knowledge by exploring new focus points and questioning existing theories.

Definition: Case Study

A case study is an in-depth study of a particular phenomenon, subject or group. The study usually employs qualitative methods, although quantitative analysis may be used to measure the relationship between some variables. Case studies document every aspect of the target group or phenomenon to achieve a granular understanding through research.2

Types of case studies

There are 6 types of case studies in research. These are:

  1. Illustrative – It is used to study a known phenomenon to make it easier to understand. It is one of the primary case studies which utilizes a descriptive approach to explain a phenomenon using one or more scenarios.
  2. Exploratory – It is an initial study conducted before the main study. Exploratory case studies are used in social sciences and focus on real-life scenarios. They are conducted to help in the formulation of research questions for complex studies.
  3. Cumulative – It is primarily used in qualitative research. It can be classified as a type of data analysis. The purpose of the case study is to analyze information from existing sources to gain insights into a research problem.
  4. Critical instance – It evaluates an event’s cause and effect. A critical case study investigates one or two instances to understand one occurrence rather than generalizing the situation. The case study can also be deployed to cross-examine a universal opinion.
  5. Descriptive – You can use a descriptive case study to build on a hypothesis. It may be used in quantitative research to ascertain relationships between a theory and the subject of a research project.
  6. Intrinsic – Mainly focuses on a single subject to understand their interaction with factors around them. It is often used in psychology and healthcare research to study individuals and their unique characteristics.3

Case studies can be summarized into 3 main groups for general understanding. These are:

  • Intrinsic studies to examine unique phenomena or individuals
  • Instrumental case studies to study individuals to understand a broader topic
  • Collective case studies to investigate multiple cases concurrently.4

When to perform a case study

A case study is the right research design for examining and gaining precise, contextual insights about a real-world problem or scenario. It gives researchers a method of studying the main characteristics, definitions and inferences about a case.

They are appropriate for thesis and dissertations as they narrow the focus of a project. This helps to anchor the research and save time and resources by focusing on fewer variables.

Researchers may use a single in-depth case study when investigating one subject. However, several case studies may be conducted simultaneously to draw comparisons from various variables in the research problem.5

Examples of research questions and their corresponding case studies:

Research Question Case study
What are the pros and cons of nuclear power? Case studies of three nuclear power plants situated in different locations
How does digital advertising influence the sales of services? Case study of a SaaS advertising campaign
How do young people respond to flash fashion? Case study of Nike and Supreme customers

Case Study: Step-by-step

We can break down the main steps as follows:

Step 1: Select a case

The research questions and the problem statement should present several potential cases. Choose a specific focus to ground your research. The case study should be able to:

  • Offer new insights about the subject.
  • Question or critique existing notions and assumptions.
  • Suggest practical approaches to solve a problem.
  • Propose new approaches for research in the future.

Case studies usually focus on outliers rather than deliberate sampling techniques. Thus, they often do not require representative or random samples before research.

Step 2: Build a theoretical framework

Case studies overlook general theories in favor of specific details. However, they should have some relationship with an existing theory so that the research findings contribute to the current understanding of the research subject. A theoretical framework can be used to:

  • Challenge an existing theory by investigating deviance that is not considered in the universal assumptions.
  • Expand on established theories by proposing new ideas that should be included.
  • Exemplify a given theory by showing the relationship between the case and the theory.
  • Researchers develop a theoretical framework after a literature review of relevant sources to achieve academic credibility by considering the main theories in conducting analysis.

Step 3: Collect your data

There are various research methods used in the collection of quantitative and qualitative data. Case studies are more concerned with qualitative data from interviews, examination of different literary sources and observation, although some quantitative methods can be used where necessary.

Step 4: Describe and analyze the case

You need to provide a detailed picture of the research subject by proposing a case study that incorporates the main aspects of the study. Researchers can format their findings in a thesis structure with clear sections to draw attention to analysis methods, findings and discourse.

Some case studies can be outlined in narrative prose to delve into the concepts from different perspectives and explain the definitions and consequences. Regardless of the method of presentation, it is essential to provide context and create a link between the case and the literature used in its study.

Benefits and limitations of a case study

Some of the pros and cons of case studies include:

Pros Cons
• It employs various research methods
• It is used to study real-life problems
• It is highly flexible and scalable
• It can consume a lot of resources
• It may take a long time to analyze the data
• It does not require a random or representative sample6


A case study is an in-depth investigation of a research subject, individual, or group. It is a focused research method that analyzes the causes and consequences of a determined phenomenon.

A theoretical framework highlights the relevant concepts in a research theory to guide the study. It also informs the literature review process of existing primary and secondary sources of information.

A case study is used to examine real-world situations. Researchers formulate case studies to identify and investigate real scenarios using existing sources and research problems that aim to study outliers of a research subject.

Case studies are deployed in social sciences and fields such as psychology and healthcare research. They are used to provide focused conclusions in complex research problems.


1 Cherry, Kendra. “What Is a Case Study?.” Verywellmind. July 22, 2022.

2 Salmon, Lauren. “The importance of case studies in social research.” Changeworks. May 23, 2017.

3 Allison, Nova. “Understand the Basic Types of Case Study Here.” Myperfectwords.

4 Dr. Paulus. “Different Types of Case Study.” Papersowl. November 24, 2021.

5 Copypress. “When and How to Use a Case Study for Research.”  May 17, 2022.

6 Miller, Brandon. “7 Pros and Cons of Case Studies.” GreenGarage. August 30, 2016.