To the Editor Folmer and colleagues1 found that treating chronic tinnitus with repetitive transcranial magnetic stimulation (rTMS) resulted in a significantly increased response rate compared with placebo treatments.1 Perception of tinnitus may be altered by the placebo effect, so the success of maintaining blinding was assessed at the end of the study by asking each patient whether they believed they had been treated with rTMS or placebo. Their eTable 12 discloses that, of the 22 patients who guessed that they received active rTMS, exactly 50% (11) guessed correctly. Likewise, of the 42 patients who guessed they received placebo, exactly 50% (21) guessed correctly. The authors1 claim that these data demonstrate that blinding was maintained because the patients in each subgroup guessed with the 50% accuracy of a coin flip.
Keller DL. Assessment of Blinding in a Tinnitus Treatment Trial. JAMA Otolaryngol Head Neck Surg. 2015;141(11):1031. doi:10.1001/jamaoto.2015.2425