another descriptive is called? in which ? individual is studied in great details

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Studying one individual in great detail is called a case study.

Another term for a detailed study of an individual is called a case study. In a case study, a particular person, group, or situation is analyzed in-depth to obtain a comprehensive understanding of their experiences, behavior, and potential influences. In this type of research, multiple sources of information are typically gathered, including interviews, observations, documents, and sometimes psychological assessments. The aim is to provide rich, detailed, and context-specific insights into the subject being examined. Case studies are commonly used in various disciplines such as psychology, sociology, and anthropology.