CASE STUDIES
SPECIFICATION: Case Studies
NON-EXPERIMENTAL METHODS IN PSYCHOLOGY
CASE STUDY
DEFINITION
A case study thoroughly analyses a particular case (or cases) within a real-world context. For example, case studies in psychology may focus on an aspect of the individual, a psychiatric condition, brain injury or an unusual up-bringing. Case studies can also highlight aspects of a group, organisation, event, belief system, or action, such as examining a particular psychiatric institution.
The purpose of a case study is to provide a detailed analysis of an individual, establishment or real‐life event. A case study does not refer to how the research was conducted, as case studies can use experimental or non‐experimental methods to collect data.
Case studies are often used where a rare behaviour is being investigated that does not arise often enough to warrant a larger study being conducted. A case study allows data to be collected and analysed on something psychologists do not understand and can, therefore, be the starting point for further, more in‐depth research.
A case study does not have to be a single observation. Still, it may include several observations (one or multiple individuals and situations across many periods, all concerning the same case study.
Research projects involving more than one case study are called cross-case research, whereas a single case study is called within-case research. The latter involves the study of an individual, small group, institution or event.
A case study encompasses many techniques, including observations, questionnaires, surveys, interviews, testing and even, on occasion, experiments. They are frequently longitudinal and may also involve asking others, such as friends and associates.
EXAMPLES
Clive Wearing, HM, KF, S, Genie Wiley, Czech twins, Anna O, Little Albert, Little Hans, Phineas Gage, Louis Leborgne, Charles Whitman.
ADVANTAGES
They provide a wide variety of in-depth and detailed information that would be impossible to acquire using heavily controlled situations such as experiments (idiographic). They can provide a real feel for suffering from a particular disorder or being involved in a certain situation.
Allows detailed investigation into situations. They often provide the only method possible for studying a certain condition or event. It would not be possible to re-create situations such as Genie or HM experimentally artificially, so our only access to information about privation or severe amnesia is through case studies.
A strength of the case study approach is that it offers the opportunity to unveil rich, detailed information about a situation. These unique insights can often be overlooked in situations where only one variable is manipulated to measure its effect on another. Further, case studies can be used in circumstances that would not be ethical to examine experimentally.
DISADVANTAGES
Often, case studies require retrospective data collection, with parents, friends, etc., being asked to think back to the participants’ earlier years. Retrospective data collection is not reliable.
Objectivity and researcher bias can be difficult, with psychologists getting too close to patients, as in the case of David Rigler and Jean Butler and their research/fostering of Genie.
Confidentiality can be an issue, though some can be overcome using pseudonyms or initials.
There are methodological issues associated with the use of case studies. By only studying one individual, an isolated event or a small group of people, it isn't easy to generalise any findings to the wider population since results are likely unique. Therefore, this creates issues with external validity as psychologists cannot confidently conclude that anyone beyond the ‘case’ will behave in the same way under similar circumstances, thus lowering population validity. Case studies, by their very nature, are one-offs or unusual and often involve people who are not themselves representative of the general population. The case of Genie and the Czech twins shows this nicely. Both suffered severe deprivation over a prolonged period, but their outcomes are very different; the Czech twins seemed to make a full recovery, whereas, as far as we know, Genie never recovered from her early problems.
An issue in case studies, particularly where qualitative methods are used, is that the researcher’s subjectivity may pose a problem. For example, in the case study of Little Hans, Freud developed an entire theory based on what he observed. No scientific or experimental evidence from his case study supported his suggestions. A major problem with his research is that we cannot be sure he objectively reported his findings. Consequently, a major limitation of case studies is that research bias and subjectivity can interfere with the validity of the findings/conclusions.
CASE STUDIES DON’T SHOW CAUSE-AND-EFFECT RELATIONSHIPS
Phineus Gage - We can’t assume that all individuals will suffer the same cognitive defects after frontal lobe injury as Phineus Gage did.
Genie - We can’t assume all privated babies will behave like Genie.
David Reimer Twins - We can’t assume that all individuals will reject the gender they were not assigned at birth.
Charles Witman - We can’t assume that all individuals with tumours on the amygdala will go on a psychopathic killing spree.
Paul Leborgne - We can’t assume all individuals will lose speech if they damage the left frontal lobe.
EXAM QUESTIONS
1. Researchers often use various techniques to gather information in case studies of individuals, institutions or events. Suggest one technique which the psychologist could use in a case study. (1 mark) Exam Hint: Referring to the use of meta‐analysis here would not be appropriate: be specific and name an
experimental or non‐experimental research method (e.g. interview).
2. Define the key term ‘case study’. (2 marks)
Exam Hint: Better answers will refer to the fact that a case study is an in‐depth investigation of a single person, usually over time, using various methods to collect data. Students can also illustrate their answers with relevant examples, such as Freud’s Little Hans Case Study.
3. Explain one limitation of using a case study as a method of investigation. (2 marks)
Exam Hint: Most students will explain a lack of population validity here: since a case study is of a unique person, it is difficult to generalise the results to the wider population as they may not behave in the same way.
Explain one strength of using a case study methodology in psychology. (3 marks)
Scarlett has an incredible memory. She can see a pack of playing cards only once and then recall the order correctly. A psychologist was interested in investigating this phenomenon further by focusing on Scarlett and her amazing memory in different situations and contexts.
The scenario illustrated above is an example of a case study methodology. Explain one strength and
one weakness of this research method. (4 marks)
Exam Hint: For this question, there is one mark each for identifying one appropriate strength and one appropriate weakness, and the third and fourth marks come from suitable elaboration of these points. For example, a strength of using a case study to study memory is that the data gathered will be rich in detail, which will give a unique insight into the individual case of Scarlett and her memory.
6. Evaluate the use of case studies in psychological research. Refer to evidence in your answer. (6 marks)
