The standard way to assess medical technologies is to conduct a randomized clinical trial. Patients are randomly assigned to groups receiving alternative treatments, and outcomes are monitored over a long period of time. Randomized clinical trials provide invaluable knowledge about the outcome of medical technologies, but they suffer from several disadvantages. They are time-consuming and expensive, sample sizes are limited, and results from multiple trials may be contradictory. In addition, randomized trials are often performed under ideal rather than usual circumstances, and thus their results must be generalized cautiously. In order to judge appropriateness, a method that combines data from trials and other studies with the opinions of experts is needed. This Note describes such a method, and discusses its application to rate the appropriateness of six medical and surgical procedures — coronary angiography, coronary artery bypass surgery, cholecystectomy, upper gastrointestinal endoscopy, colonoscopy, and carotid endarterectomy.