The Case-Control Method in Medical Care Evaluation

The case-control method has been applied extensively to the study of chronic diseases, largely because of its advantage in cost and statistical power over other study designs. However, problems in ensuring the validity of case-control results have led to certain reservations regarding the general utility of the method. We discuss how several of the major validity problems in case-control studies of chronic disease are limited or absent in case-control evaluations of medical care and medical technology. As a consequence, the case-control method has important potential for application in evaluation and technology research.