Effects of different electrical stimulation on depression: a systematic review and network meta-analysis

Background Depression is a prevalent psychiatric disorder characterised by persistent low mood and anhedonia, substantially impairing quality of life. Conventional treatments show variable efficacy and tolerability, with high post-discontinuation relapse rates. Electrical stimulation has emerged as an alternative intervention, but comparative efficacy and safety of different modalities remain uncertain. This systematic review and network meta-analysis aimed to synthesise evidence and quantitatively compare electrical stimulation approaches for depression. Methods A systematic search of 13 databases was conducted for randomised controlled trials (RCTs) published from inception to 16 July 2026. Methodological quality and risk of bias were assessed using the Cochrane RoB 2 tool, and certainty of evidence was evaluated with the GRADE framework. Frequentist network meta-analysis was performed using STATA 18.0. Publication bias was assessed via funnel plot inspection, and sensitivity analyses examined the robustness of findings. Results A total of 33 RCTs involving 2,664 participants and nine electrical stimulation modalities were included. Pairwise meta-analysis showed that electrical stimulation was associated with a significantly improved clinical response rate (OR = 2.78, 95% CI 1.50 to 5.16) and a reduction in depressive symptom severity (SMD = −0.90, 95% CI −1.27 to −0.54) among patients with depression, along with a favourable safety profile (OR = 0.88, 95% CI 0.52 to 1.49). However, therapeutic effects varied across modalities. Specifically, Transcutaneous auricular vagus nerve stimulation (taVNS) ranked highest for improving the clinical response rate (SUCRA = 99.9%; OR = 4.12, 95% CI 3.08 to 5.16), whereas transcranial direct current stimulation (tDCS) ranked highest for reducing the Hamilton Depression Rating Scale (HAMD) score (SUCRA = 71.3%; SMD = −1.70, 95% CI −2.80 to −0.60). Sensitivity analyses confirmed the robustness of these results. Conclusions Electrical stimulation is associated with improved clinical response rates and reduced depressive symptom severity in patients with depression, and is generally well tolerated. Among the modalities examined, taVNS demonstrated a relative advantage in improving clinical response, while tDCS showed a relative advantage in alleviating depressive symptom severity. However, given the low certainty of the evidence underpinning these findings, they require confirmation in larger, higher-quality randomised controlled trials. Systematic Review Registration [url], identifier CRD420251103264.