A case study is a research approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life context. It is an established research design that is used extensively in a wide variety of disciplines, particularly in the social sciences. A case study can be defined in a variety of ways..., the central tenet being the need to explore an event or phenomenon in depth and in its natural context.
Crowe, S., Cresswell, K., Robertson, A. et al. The case study approach. BMC Med Res Methodol 11, 100 (2011). https://doi.org/10.1186/1471-2288-11-100