Considerations and Methods for Placebo Controls in Surgical Trials (ASPIRE Guidelines)

Placebo comparisons are increasingly being considered for randomised trials assessing the efficacy of surgical interventions. The aim of this paper is to provide a summary of current knowledge on placebo controls in surgical trials. A placebo control is a complex type of comparison group and, although powerful, presents many challenges in a surgical setting. This review outlines what a placebosurgical control entails and our understanding of the placebo phenomenon in the context of surgery. It considers when placebo-surgical controls are acceptable (and when they are desirable) in terms of ethical arguments and regulatory requirements, how a placebo-surgical control should be designed, how to identify and mitigate risk for participants in placebo surgical trials, how such trials should be conducted and interpreted. Use of placebo control is justified in randomised controlled trials of surgical interventions provided there is a strong scientific and ethical rationale. Surgical placebos may be most appropriate where there is poor evidence on the efficacy of the procedure and a justified concern that results of a trial would be associated with high risk of bias, particularly due to the placebo effect. Feasibility work is recommended to optimise RCT design and conduct. This review forms an outline for best practice and provides guidance, in the form of the ASPIRE (Applying Surgical Placebo in Randomised Evaluations) checklist, for those considering the use of a placebo-control in a surgical randomised controlled trial.