The lower boundary of the confidence interval for the difference in the decrease for tDCS versus escitalopram (difference, −2.3 points; 95% CI, −4.3 to −0.4; p=0.69) was lower than the pre-defined noninferiority margin of −2.75 so noninferiority could not be claimed.
An editorial discusses limitations of the study and notes that although uncertainty remains regarding the antidepressant efficacy of tDCS, the study shows key knowledge gaps in the dose–response relationship and physiologic mechanisms for tDCS and other forms of noninvasive brain stimulation that need to be addressed in order for an effective therapy to be developed.