Case studies are in-depth investigations of a single person, group, event, or community. Typically, data are gathered from a variety of sources and by using several different methods (e.g. observations & interviews). The case study research method originated in clinical medicine (the case history, i.e. the patient’s personal history). In psychology, case studies are often confined to the study of a particular individual.
The information is mainly biographical and relates to events in the individual’s past (i.e. retrospective), as well as to significant events which are currently occurring in his or her everyday life.
The case study is not itself a research method, but researchers select methods of data collection and analysis that will generate material suitable for case studies.
How is a case study conducted?
The procedure used in a case study means that the researcher provides a description of the behavior. This comes from interviews and other sources, such as observation.
The client also reports detail of events from his or her point of view. The researcher then writes up the information from both sources above as the case study and interprets the information.
The research may also continue for an extended period of time, so processes and developments can be studied as they happen.
Amongst the sources of data the psychologist is likely to turn to when carrying out a case study are observations of a person’s daily routine, unstructured interviews with the participant herself (and with people who know her), diaries, personal notes (e.g. letters, photographs, notes) or official document (e.g. case notes, clinical notes, appraisal reports).
The case study method often involves simply observing what happens to or reconstructing ‘the case history of a single participant or group of individuals (such as a school class or a specific social group), i.e. the idiographic approach.
The interview is also an extremely effective procedure for obtaining information about an individual, and it may be used to collect comments from the person’s friends, parents, employer, workmates, and others who have a good knowledge of the person, as well as to obtain facts from the person him or herself.
Most of this information is likely to be qualitative (i.e. verbal description rather than measurement) but the psychologist might collect numerical data as well.
How to analyze case study data
The data collected can be analyzed using different theories (e.g. grounded theory, interpretative phenomenological analysis, text interpretation, e.g. thematic coding).
All the approaches mentioned here use preconceived categories in the analysis and they are ideographic in their approach, i.e. they focus on the individual case without reference to a comparison group.
Interpreting the information means the researcher decides what to include or leave out. A good case study should always make clear which information is the factual description and which is an inference or the opinion of the researcher.
Strengths of Case Studies
- Provides detailed (rich qualitative) information.
- Provides insight for further research.
- Permitting investigation of otherwise impractical (or unethical) situations.
Case studies allow a researcher to investigate a topic in far more detail than might be possible if they were trying to deal with a large number of research participants (nomothetic approach) with the aim of ‘averaging.
Because of their in-depth, multi-sided approach case studies often shed light on aspects of human thinking and behavior that would be unethical or impractical to study in other ways.
Research which only looks into the measurable aspects of human behavior is not likely to give us insights into the subjective dimension to experience which is so important to psychoanalytic and humanistic psychologists.
Case studies are often used in exploratory research. They can help us generate new ideas (that might be tested by other methods). They are an important way of illustrating theories and can help show how different aspects of a person’s life are related to each other.
Limitations of Case Studies
- Lacking scientific rigor and providing little basis for generalization of results to the wider population.
- Researchers’ own subjective feelings may influence the case study (researcher bias).
- Difficult to replicate.
- Time-consuming and expensive.
- The volume of data, together with the time restrictions in place, impacted the depth of analysis that was possible within the available resources.
Because a case study deals with only one person/event/group we can never be sure if the case study investigated is representative of the wider body of “similar” instances. This means the conclusions drawn from a particular case may not be transferable to other settings.
Because case studies are based on the analysis of qualitative (i.e. descriptive) data a lot depends on the interpretation the psychologist places on the information she has acquired.