Baseline characteristics of patients.

aContinuous data are expressed as mean ± SD.bAuricular acupuncture was included.cThe use of medications did not exceed one week.dOne patient received a combination of SNRIs and mood stabilizers.n-EA, noninvasive electroacupuncture; DCEAS, dense cranial electroacupuncture stimulation; MDD, major depressive disorder; SSRIs, selective serotonin re-uptake inhibitors; SNRIs, Serotonin–norepinephrine reuptake inhibitors; HAMD, 17-item Hamilton Rating Scale for Depression; CGI-S, Clinical Global Impression-Severity; SDS, Self-rating Depression Scale.