The Double-Blind Randomized Controlled Trial as the Gold Standard in Psychedelic Research: Neither Feasible Nor Desirable.

Double-blind, randomized, controlled trials (DB-RCTs) are often considered the gold standard for establishing causal efficacy in medical research, but they face unique challenges when applied to psychedelic-assisted therapy (PAT). Participants can often guess whether they received a psychedelic due to its psychoactive effects, which may bias results through expectancy and experimenter behavior. This paper argues that the DB-RCT design should be abandoned as the assumed gold standard in PAT research because its logic is undermined by the intervention and it neglects important extrapharmacological factors. Instead, DB-RCTs should be seen as producing complementary, not superior, results to other research designs, allowing a more holistic study of PAT.

Study at a glance

Abstract

Double-blind, randomized, controlled trials (DB-RCT), if designed and conducted well, are widely considered the gold standard in medical research for purposes of establishing causal efficacy. Their logic is compelling: by balancing out all confounding variables through the research design, DB-RCTs are thought to reveal whether a proposed treatment-by virtue of its characteristic constituents-causes therapeutic effects. Many studies on psychedelic-assisted therapy (PAT) follow this ostensible gold standard and use a DB-RCT design. But several authors have already noted that conducting psychedelic DB-RCTs is particularly challenging: due to the psychoactive effects of psychedelics, participant awareness of condition assignment is likely; this awareness may then interact with response expectancy and experimenter behavior, introducing systematic bias into the trial. For this reason, these authors have suggested ways to rescue DB-RCTs for PAT. This paper takes a different direction. It argues that we should abandon the DB-RCT design as the assumed gold standard in PAT research, because its logic is largely undermined by the intervention(s) in question, and the design in its standard form neglects potentially important aspects of PAT (i.e., extrapharmacological factors and their interaction(s) with the psychedelic). Abandoning DB-RCT opens the door to a more holistic study of PAT, in which DB-RCTs are still useful for certain ends but are considered to produce results that are not per se superior but complementary to those of other research designs.