Blinding, Expectancy, and the Active Placebo Paradox in MDMA Research.
Psychopharmacology (Berl) June 13, 2026 Mitch Earleywine, Quinn Allen
The text examines how blinding and expectancy effects complicate placebo-controlled trials of MDMA, introducing the concept of an 'active placebo paradox.' It argues that the strong subjective effects of MDMA make true blinding nearly impossible, which can inflate treatment effects and undermine causal inference. The authors suggest that expectancy and unblinding may account for a substantial portion of the therapeutic outcomes reported in MDMA research, raising questions about the validity of findings from such trials.