Impact of randomized clinical trials on medical practices.

The randomized clinical trial (RCT) is the most powerful tool available to assess the effectiveness of a medical procedure. It complies with the fundamentals of scientific human experimentation and it is accepted, as such, by the researchers as the yardstick of medical progress. Therefore RCTs should have had a major impact on current medical practices through health policy makers and prescribers. Though they are limited in number and they have investigated few medical fields, studies on the impact of RCTs on medical practice have shown large and frequent discrepancies between scientific data made available from RCTs and current prescription practices in France, the United States, Finland, Holland, and elsewhere. Hence the above expectation is frustrated because doctors are not trained to weigh the evidence on treatment benefit-risk ratios, to read clinical research reports, or to select the appropriate information. In addition, the number of pending problems addressed by RCTs are too few, too slow to give the answers, inadequately sized, and their outcome measures are more often than not inappropriate. Doctors are reluctant to participate in clinical trials despite such participation being one of their duties. Governmental agencies barely fund clinical trials. Researchers do not formulate the right questions.