title: Blinding success of rTMS applied to the dorsolateral prefrontal cortex in randomised sham-controlled trials: a systematic review.
abstract: OBJECTIVE
  The lack of a suitable sham condition for repetitive transcranial magnetic stimulation (rTMS) research may compromise the success of blinding procedures. The aim of this systematic review was to examine the reporting of blinding success in randomised sham-controlled trials (RCTs) of rTMS applied to the dorsolateral prefrontal cortex.
  
  
  METHODS
  A literature search using Pubmed and Web of Science was conducted to identify RCTs of rTMS. Regression analyses were used to investigate whether participants in the real and sham rTMS groups differed in (1) their ability to correctly guess to which intervention they had been randomised, and (2) how likely they were to think they had received real rTMS.
  
  
  RESULTS
  Thirteen out of 96 (13.5%) RCTs reported blinding success. Available data from 9/13 studies showed that participants in real and sham rTMS groups were not significantly different in their ability to correctly guess their intervention allocation, but with a trend for participants in the real group to more often guess correctly. However, people in the real rTMS groups were significantly more likely to think they had received real rTMS compared with those in sham rTMS groups.
  
  
  CONCLUSIONS
  Few RCTs in rTMS report on blinding success. As current sham methods may inadequately mimic real rTMS, this could result in only partial success of blinding and bias estimations of treatment effects.
authors.affiliation: King's College London, Institute of Psychiatry, Section of Eating Disorders, London, UK.
authors.forename: Hannah J
authors.initials: HJ
authors.lastname: Broadbent
authors.forename: Frederique
authors.initials: F
authors.lastname: van den Eynde
authors.forename: Sebastien
authors.initials: S
authors.lastname: Guillaume
authors.forename: Emma L
authors.initials: EL
authors.lastname: Hanif
authors.forename: Daniel
authors.initials: D
authors.lastname: Stahl
authors.forename: Anthony S
authors.initials: AS
authors.lastname: David
authors.forename: Iain C
authors.initials: IC
authors.lastname: Campbell
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schmidt
mesh_terms: D003866:Depressive Disorder / Q000628:therapy*; D004311:Double-Blind Method; D006801:Humans; D015990:Placebo Effect; D017397:Prefrontal Cortex; D016032:Randomized Controlled Trials as Topic; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome