Do medical devices have enhanced placebo effects?

Although the placebo in a clinical trial is often considered simply a basel ine against which to evaluate the efficacy of a clinical intervention, ther e 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 impli cations may be, While the evidence of an enhanced placebo effect remains ru dimentary, it is provocative and therefore worthy of further study. Suggest ions are made, therefore, for how such an effect can be investigated withou t violating the principles of informed consent. (C) 2000 Elsevier Science I nc. All rights reserved.