Excess Significance Bias in Repetitive Transcranial Magnetic Stimulation Literature for Neuropsychiatric Disorders.

Introduction: Repetitive transcranial magnetic stimulation (rTMS) has been widely tested and promoted for use in multiple neuropsychiatric conditions, but as for many other medical devices, some gaps may exist in the literature and the evidence base for the clinical efficacy of rTMS remains under debate.

Objective: We aimed to test for an excess number of statistically significant results in the literature on the therapeutic efficacy of rTMS across a wide range of meta-analyses and to characterize the power of studies included in these meta-analyses.

Methods: Based on power calculations, we computed the expected number of "positive" datasets for a medium effect size (standardized mean difference, SMD = 0.