What is the design of a case-control study?

In a case-control study, researchers focus on comparing two distinct groups defined by their outcome status. Specifically, one group consists of individuals who have the outcome of interest (the cases), while the other group includes individuals who do not have the outcome (the controls). Through this design, researchers can retroactively examine various exposures or risk factors that may contribute to the presence of the outcome in the "cases" compared to those in the "controls."

This design is particularly advantageous for studying rare conditions since it allows for the efficient comparison of exposures between a small number of individuals with the condition and a larger group without it, avoiding the lengthy process of following a large cohort over time that may not develop the condition. Case-control studies often yield valuable insights and can be completed relatively quickly, making them a popular choice in epidemiological research.