Comparison of psychological placebo and waiting list control conditions in the assessment of cognitive behavioral therapy for the treatment of generalized anxiety disorder: a meta-analysis

摘要

BackgroundThere is ongoing debate about the efficacy of placebos in the treatment of mental disorders. In randomized control trials (RCTs) about the treatment of generalized anxiety disorder, the administration of a psychological placebo or placement on a waiting list are the two most common control conditions. But there has never been a systematic comparison of the clinical effect of these different strategies.