Deception in research on the placebo effect

Abstract

This chapter examines ethical issues relating to the use of deception in research on the placebo effect, with particular emphasis on experiments involving patients in clinical settings. The placebo effect is a fascinating yet puzzling phenomenon, defined as the “positive physiological or psychological changes associated with the use of inert medications, sham procedures, or therapeutic symbols within a healthcare encounter.” Increasing scientific inquiry has been aimed at elucidating the mechanisms responsible for placebo effects and determining how inert interventions can lead to positive changes in patients. Patients' expectations for improvement, known as “response expectancies,” are thought to be one of the central mechanisms responsible for placebo effects. The chapter first considers why deception in scientific investigation is ethically problematic before presenting examples of deception in placebo research. It then proposes a method of informing participants about the use of deception that can reconcile the scientific need for deceptive research designs with the ethical requirements for clinical research.