Eight RCTs were included (n=477).
Three studies scored 5 out of 5 on the Jadad scale; the other studies scored 3. Five studies reported randomisation methods, seven were double-blinded, five reported reasons for withdrawals and four used intention-to-treat analysis. Drop-out rates ranged from 6% to 33%.
Acupuncture was associated with a statistically significant reduction in depression scores compared to sham acupuncture (standardised mean difference -0.65, 95% CI: -1.18 to -0.11, p=0.02; seven studies). Significant heterogeneity was found (p<0.00001, I2=84.1%). Depression scores were also significantly reduced in patients with major depression (six studies) and depressive disorder (one study). Results were similar and significant heterogeneity remained after excluding each study in turn. There was no evidence of publication bias from the funnel plot or Egger’s test (p=0.84).
There was no statistically significant difference between active and sham acupuncture in response rates (six studies) or remission rates (four studies). Significant heterogeneity was found for both analyses (p=0.006, I2=69.7% and p=0.03 and I2=67.9%).