An epidemiological study in which the risk factors of people with a certain disease (cases) are compared with those without the disease (controls).
a technique which is used in epidemiology. The technique identifies individuals who have a disease (cases) and individuals who do not have the disease (controls). Something which is present in cases, but not in controls, is connected with the disease.
A case-control study is a common type of epidemiologic study. Two groups of people are selected based on the presence or absence of a disease or specific health problem of interest. Individuals in one group have the disease or health problem; individuals in the other group do not. Information is collected in the same way from individuals in both groups regarding specific exposures they have experienced in the past, and/or personal characteristics that might have caused the disease. The two groups are then compared to determine the degree to which the exposures or characteristics of interest are related to the development of the disease or health problem under study.