| [ Summary ] |
Case-control studies are types of epidemiological observational studies. Observational studies are ones in which subjects are not randomized to the exposed or unexposed groups, rather the subjects are observed in order to determine both their exposure and their outcome status and the exposure status is thus not determined by the researcher. Controls should come from the same population as the cases, and their selection should be independent of the exposures of interest. Case-control studies are a relatively inexpensive and frequently used type of epidemiological study which can be carried out by small teams or individual researchers in single facilities in a way that more structured experimental studies often cannot be. An example is described wherein a case-control study is used to solve a problem in a dialysis facility. |