Case-control Studies

Case-control studies are an epidemiological research tool used to assess the relationship between an exposure (i.e. a risk factor) and an outcome (i.e. disease). They are observational studies that compare the proportions of exposed and unexposed individuals within two populations that are similar in all other factors. This type of study compares individuals with the given outcome (the 'cases') to those without the outcome (the 'controls') and examines the association of the exposure status between the two groups. By comparing the proportion of exposed individuals within the cases to the control group, and measuring the differences in outcome between the two groups, researchers can assess the potential cause and effect relationship between the exposure and the outcome. Case-control studies are cost and time-efficient, which allows them to yield results quickly, and are useful for researching the rare or hard to diagnose diseases.