I rest my case… study.

by Research Methods & Statistics

This week, I’m going to focus on case studies. Firstly, we’ll discuss key their concepts, role in psychology and history. Finally, we shall discuss the strengths, weaknesses and ethics with examples along the way.

Case studies involve an in-depth study, analysis and detailed description of a single individual/very small group of people involving a treatment/therapy administrated by researchers. Descriptions are filed in a report consisting of observation analyses, individual’s details and effects of therapy administrated. Information used in case studies can be gathered in numerous ways, most of them are qualitative methods e.g.

  • Observations
  • Interviews (semi-structured)
  • Diaries and personal notes
  • Secondary sources – blogs, archives etc.

Psychological research tends to focus on groups opposed to single individuals. Whilst studying groups as a whole is useful in some aspects of psychology, other areas centre more on individualistic behaviour. Allport (1961)1 argues the idiographic approach of case studies is as important as the study of groups. I agree and I’ll explain why…

When brain-storming the history of case studies one name springs to mind… Freud! Freud (1901;1965)2 relied heavily on case studies presenting them as a huge part of psychoanalytical theory e.g. Little Hans3 and Anna O4. I blame Freud for the discredit of case studies. Whilst his work undoubtedly had an enormous impact in psychology, leading many psychologists to develop modification of his theories his work still provokes debates 70 years after his death. Eysenck (1952)5 argued Freud used case studies to make exaggerated claims regarding human behaviour such as that of Little Hans. This was the only evidence Freud provided in his theory of phobias. As case studies contain details regarding one person so results and observations may not generalise to the population and may not be a causal explanation of human behaviour. We cannot assume that every individual behaves the same. By using case studies Freud’s work can be criticized for lacking objectivity as his interpretation of results may be a result of his expectations. So; Freud’s use of case studies… not so good!

But case studies stem much further than Freud. Early case studies into other areas of psychology e.g. developmental and neuropsychology are helpful such as the case of David Reimer (Money & Ehrhardt, 1972)6. Originally born as a boy, David lived as a girl after a mishap during circumcision in which his penis was destroyed. Researchers advised David’s parents he could successfully live as a girl; they believed that nurture (environment & social factors) shaped gender rather than nature (biology). However, through a longitudinal case study (following David living as a girl throughout childhood) it became clear that this was not the case as David was severely unhappy living as a girl and when he had the chance, went back to being a boy. This case study with the use of detailed descriptions, observations and interviews longitudinally strongly contradicted the idea of gender being shaped by the environment which in turn led to an increase in psychological knowledge about gender.

It may come as a shock but scientists also use case studies. Neuropsychology presents the case study of Phineas Gage (Valenstein, 1986)7 who received damages to the frontal lobes of his brain in an accident where an iron rod was forced through his skull.

This case increased scientific understanding of functions in the human brain by being the first to illustrate how damage to specific areas of the brain may change personality. This early case reinforces the importance of case studies within psychological research as it may not be so ethical to push iron rods in people’s heads to see the effects of such actions.

Applications and the history of case studies suggest that case studies are very helpful within many of areas of psychology. Imagine batman without robin; not good! Similarly, psychology without case studies wouldn’t be great either.

The main advantage of case studies is the intense amount of detail. Case studies are thought to be an ideal research methodology when a holistic, in-depth and detailed investigation is required (Feagin, Orum & Sjoberg, 1991)8. They highlight huge varieties of differential variables, events and responses which may be overlooked or eliminated by researchers in experiments as they would have been seen as an extraneous variable. Therefore, a case study can pin point new variables which may explain a particular outcome thus establishing a new future research hypothesis. Secondly, they can demonstrate exceptions to the rule. For example David Reimer, this one example was enough to demonstrate that gender is not always shaped by the environment as predicted by researchers. Case studies show that a predicted law of behaviour isn’t always true. They also provide unusual situations and unique variables which may not be possible to study in experimentation due to ethics. For example, in developmental psychology the case study of Genie9 proved to be extremely useful. Researchers cannot set up an experiment in a controlled environment about the effects of being abused and privation as a child as they would be arrested. However, case studies allow researchers to explore such untestable concepts and review the long term effects.

We cannot ignore limitations of case studies. They simply describe behaviours observed and fail to show underlying mechanisms to explain behaviours. So, detailed information such as a participant’s age, gender and background are gathered but no explanation of these variables is offered. Whilst case studies offer some explanation of observations there are always other possible factors, this refers to low internal validity. Furthermore, case studies lack external validity by focusing solely on one person/group therefore it’s hard to generalise the results from that unique person. This problem can be reduced by replication; case studies can be accompanied by similar reports this increasing external validity.

It’s important to consider the well fair of the individual being studied therefore case studies are regulated by ethical guidelines*. When the individual is being interviewed or writing a diary as a self-reflective measure they are likely to experience negative feelings by discussing traumatic parts of their life, this refers to the principle of protection of participants against psychological harm. As case studies are concerned with a person’s life events researchers need to be sensitive to the principles of confidentiality, anonymity and protection of participants. If researchers remain sensitive and professional offering debriefing and psychological help along the way then ethics shouldn’t be too much of an issue.

In conclusion case studies have been helpful throughout history especially in developmental (privation and gender) and neuropsychology and psychoanalysis (to some extent) and to this day are still a vital research method. Whilst some argue case studies lack validity this can easily be overcome by replicating to find similar findings to back up case studies (an approach Freud should have adopted!) By producing detailed data through a variety of different research techniques, having the ability to pin point new research ideas and meeting necessary ethical guidelines the importance of case studies cannot be dismissed just because some fail to see them as unscientific.


1 Allport, G. W. (1961). Pattern and growth in personality. New York: Holt, Reinhart, and Winston.

2 Freud, S. (1901;1965). The psychopathology of everyday life. London: Hogarth Press.

 3 Freud, S. (1909). Analysis of phobia in a five-year-old boy. The complete psychological works of Sigmund Freud: The standard edition, Volume 10. New York: W.W. Norton and Co.

4 http://www.freudfile.org/psychoanalysis/annao_case.html

 5 Eysenck, H. J. (1970). The structure of human personality (3rd edn). London: Methuen.

 6 http://www.youtube.com/watch?v=3GhbVFjIaN0

 7 http://www.sciencemag.org/content/264/5162/1102.short

 8 http://www.nova.edu/ssss/QR/QR3-2/tellis1.html

9 http://www.unsolvedmysteries.com/usm433991.html

 * http://www.bps.org.uk/what-we-do/ethics-standards/ethics-standards