Blinding, Placebo Effect, and GRADE Methodology

Placebo-controlled trials are commonly performed in medication studies. Due to ethical and practical concerns, this type of double blinding with the use of a “sham” procedure is not often seen or ethical in surgical research. Non–placebo-controlled trials may run the risk of overestimating efficacy of procedural interventions by the nature of their design. In this issue of JAMA Surgery, Rajkumar and colleagues recognized this problem and performed a systematic review and meta-regression to compare all available placebo-controlled trials on procedural interventions with their unblinded (non–placebo-controlled) counterparts. Although the systematic review by Rajkumar et al suffers from major clinical heterogeneity, significant larger standard ized effect sizes are found for non–placebo-controlled trials than placebo-controlled trials of procedural interventions for exercise-related, quality of life, and health care professional–assessed end points. They point out the need for placebo-controlled trials for these types of end points, t hereby reducing the potential for effect overestimation. Conversely, no significant placebo effect was found for patient-reported end points, blood pressure, mortality, pain, and recurrent bleeding events.
Source: JAMA Surgery - Category: Sports Medicine Source Type: research