What is a case study and why might a psychologist choose to use this research method?

A case study is an in-depth analysis of the experience of an individual or small group. A psychologist might opt for the case study method if they are interested in individuals with very unusual and understudied characteristics. This is because it would allow them to obtain a large amount of data about such individuals, providing a rare opportunity to deepen our knowledge about these individuals. Case studies are also used when it would be unethical to manipulate the phenomena of interest. For example, a case study was used to document the development of Genie, a child who experienced severe neglect and abuse.