Clinical benefits

Abstract

Until about 40 years ago the methodology for measuring clinical benefits relied, to an unacceptable extent, upon conclusions based on clinical impression applied in a rather pragmatic fashion. Many forms of therapy were considered beneficial on the basis more of the status and authority of the proponent, rather than upon sound experimental principles. Physicians based their treatment choice upon what they had seen happen with the same intervention in one or two previous cases. The application of the elementary principles of experimental design, based upon valid statistical principles, has revolutionized the approach to the measurement of clinical benefit. The concept of having control and treated groups, which have the same characteristics in all relevant respects, eliminated observer bias and permitted valid generalizations about clinical interventions, based upon suitable samples of a particular disease. The activity of measuring the effects of therapeutic interventions in diseases to determine clinical benefit has expanded dramatically in the intervening years, and is one of the more important activities of clinical pharmacologists. A large body of data has accumulated in many disease areas supporting, or disproving, the possible clinical benefit of a large range of interventions, including not only drugs, but surgical, manipulative and other activities.