The conduct and principles of randomized clinical trials

Abstract

Some of the guiding principles as well as the pitfall of long-term randomized clinical trials are presented. Examples have been chosen from trials in the cardiovascular field. A typical long-term clinical trial is divided into five phases: planning, preparation, recruitment, clinical follow-up and termination, and finally analysis. Administrative, legal, and ethical aspects of a trial are discussed, as well as the cost of clinical trials. Organization patterns are described and some prevalent ones are criticized. Further, practical matters such as recruitment techniques, obtaining informed consent from the patients, determining drug dosage and formulation as well as the problem of interaction with nonstudy drugs are referred to. Adherence testing remains a problem, because of our inability to test for placebo adherence.