Randomized consent designs for clinical trials: an update.

Randomized consent designs were introduced to make it easier for physicians to enter patients in randomized clinical trials. Physician reluctance to participate in randomized clinical trials is often a reflection that the physician-patient relationship could be compromised if the physician makes known to the patient his/her inability to select a preferred therapy. Clinical trials having a no-treatment control or placebo amplify this concern. This paper reviews the main ideas of randomized consent designs (single and double) and the statistical model underlying the analysis, and presents some recent experiences.