Do medical devices have enhanced placebo effects?

Although the placebo in a clinical trial is often considered simply a baseline against which to evaluate the efficacy of a clinical intervention, there is evidence that the magnitude of placebo effect may be a critical factor in determining the results of a trial. This article examines the question of whether devices have enhanced placebo effects and, if so, what the implications may be, While the evidence of an enhanced placebo effect remains rudimentary, it is provocative and therefore worthy of further study. Suggestions are made, therefore, for how such an effect can be investigated without violating the principles of informed consent. (C) 2000 Elsevier Science Inc. All rights reserved.