Case study

A case study is an in-depth, detailed examination of a particular case (or cases) within a real-world context.[1][2] For example, case studies in medicine may focus on an individual patient or ailment; case studies in business might cover a particular firm's strategy or a broader market; similarly, case studies in politics can range from a narrow happening over time (e.g., a specific political campaign) to an enormous undertaking (e.g., a world war).

Generally, a case study can highlight nearly any individual, group, organization, event, belief system, or action. A case study does not necessarily have to be one observation (N=1), but may include many observations (one or multiple individuals and entities across multiple time periods, all within the same case study).[3][4][5][6] Research projects involving numerous cases are frequently called cross-case research, whereas a study of a single case is called within-case research.[5][7]

Case study research has been extensively practiced in both the social and natural sciences.[8][9]:5–6[10][11]