Neurostimulation & neurofeedback · graded by use, two uses
Transcranial Direct Current Stimulation
Graded on: depressive symptoms in major depression on blinded clinician-rated scales (HAM-D, MADRS), mixed.
Grade C: human trials exist, but they are small, mixed or not yet repeated. This is not a finding that it does not work. How to read a grade →
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How this letter has changedLatest: October 2026 · Corrected.
The record's only citation (Li et al., 2026; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 42435147) is a network meta-analysis restricted to chronic musculoskeletal pain and does not test tDCS for depression, yet the endpoint The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score. was depression scales with no supporting trial. The record now carries the trial base: the individual patient data meta-analysis (Razza et al., 2026; PMID 41498282), SELECT-TDCS (Brunoni et al., JAMA Psychiatry, 2013; PMID 23389323) and ELECT-TDCS (Brunoni et al., N Engl J Med, 2017; PMID 28657871) as positives, DepressionDC (Burkhardt et al., Lancet, 2023; PMID 37414064), the international trial (Loo et al., Brain Stimul, 2018; PMID 29111077) and unsupervised home use (Borrione et al., JAMA Psychiatry, 2024; PMID 38170541) as large nulls, Woodham et al. (2025; PMID 39433921) as the maker-funded home-based positive, and Ren et al. (2025; PMID 40531534) finding tDCS alone not significant. Two use rows authored, clinic-administered and home-based, both C. endpoint_type corrected to clinician-rated; the not-replicated flag removed, the problem being inconsistency. Safety signals from the trials added to the page. C unchanged. Applied the written grade definition under the editor's standing instruction of October 2026 (Arnold Sandlow, D.C.).PMID 23389323 PMID 28657871 PMID 29111077 PMID 37414064 PMID 38170541 PMID 39433921 PMID 40531534 PMID 41498282 PMID 42435147
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tDCS sends a weak electric current through pads on the scalp. It has been tested for major depression, both in clinics and at home. A large pooled analysis of 18 studies and over 1,200 patients found a small benefit over a fake device. Larger studies showed smaller effects. So the benefit is real but modest.
All two uses graded on this record carry a C, each on its own evidence.
As studied, and the trials
Razza et al. (2026; PMID 41498282) pool 18 sham-controlled trials: d 0.24, smaller in larger trials. SELECT-TDCS (Brunoni et al., 2013; PMID 23389323) and ELECT-TDCS (Brunoni et al., 2017; PMID 28657871) were positive against placebo An inactive substitute made to look like the real treatment, so participants cannot tell which one they received., the latter failing noninferiority to escitalopram with two cases of new-onset mania. DepressionDC (Burkhardt et al., 2023; PMID 37414064; 160 patients, add-on to an SSRI) and the international trial (Loo et al., 2018; PMID 29111077; 130 patients) were null. Ren et al. (2025; PMID 40531534) find tDCS alone not significant in major depressive disorder. Inconsistent: C.
As studied, and the trials
Two trials disagree. Woodham et al. (2025; PMID 39433921): 174 patients, remotely supervised, 2.3 HDRS points better than sham A fake version of a procedure or device used as the comparison, so participants cannot tell which one they received. over 10 weeks, part-funded by the device's maker. Borrione et al. (2024; PMID 38170541): 210 patients, fully unsupervised, no difference from sham at 6 weeks, with one nonfatal suicide attempt in the active arm. One positive and one null: C.
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See the full evidence record →Graded on Depressive symptoms in major depression on blinded clinician-rated scales (HAM-D, MADRS), mixed.
Why this gradeGrade C, small or unreplicated trials. The reasoning, and what the grade does not cover.
Grade C on depressive symptoms in major depression, clinic-administered or home-based. Pooled sham-controlled data are positive but small: an individual patient data meta-analysis of 18 trials and 1,246 patients found Hedges' d 0.24, with larger trials showing smaller effects (Razza et al., 2026; PMID 41498282). Positive trials include SELECT-TDCS (Brunoni et al., 2013; PMID 23389323), ELECT-TDCS, which beat placebo but failed noninferiority to escitalopram (Brunoni et al., 2017; PMID 28657871), and a remotely supervised home-based trial part-funded by the device maker (Woodham et al., 2025; PMID 39433921). Large independent sham-controlled trials were null: DepressionDC at eight hospitals (Burkhardt et al., 2023; PMID 37414064), the international multisite trial (Loo et al., 2018; PMID 29111077), and fully unsupervised home use (Borrione et al., 2024; PMID 38170541). Positive meta-analyses alongside null multicenter trials is inconsistent evidence, so C.
WHAT THIS GRADE DOES NOT COVERtDCS as monotherapy, which a 2025 meta-analysis of 88 trials found not significant in major depressive disorder (Ren et al., 2025; PMID 40531534), a reading under which the letter would be D on Route 2 Human randomized trials have been run and did not show benefit on the stated outcome. One of the two routes to the lowest letter on EBL's scale.; cognitive enhancement in healthy adults; pain and anxiety, where the cited network meta-analysis found its robust effects for TMS rather than tDCS (Li et al., 2026; PMID 42435147); and TMS, graded separately. Safety signals from the trials: more mild adverse events with active stimulation, two cases of new-onset mania in ELECT-TDCS, and one nonfatal suicide attempt in the active arm of the unsupervised home-use trial.
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Each use, with its trials
This record carries a separate letter for each thing it has been measured on. The headline grade is the best of them, and it does not transfer to the others.
Razza et al. (2026; PMID 41498282) pool 18 sham-controlled trials: d 0.24, smaller in larger trials. SELECT-TDCS (Brunoni et al., 2013; PMID 23389323) and ELECT-TDCS (Brunoni et al., 2017; PMID 28657871) were positive against placebo, the latter failing noninferiority to escitalopram with two cases of new-onset mania. DepressionDC (Burkhardt et al., 2023; PMID 37414064; 160 patients, add-on to an SSRI) and the international trial (Loo et al., 2018; PMID 29111077; 130 patients) were null. Ren et al. (2025; PMID 40531534) find tDCS alone not significant in major depressive disorder. Inconsistent: C.
Two trials disagree. Woodham et al. (2025; PMID 39433921): 174 patients, remotely supervised, 2.3 HDRS points better than sham over 10 weeks, part-funded by the device's maker. Borrione et al. (2024; PMID 38170541): 210 patients, fully unsupervised, no difference from sham at 6 weeks, with one nonfatal suicide attempt in the active arm. One positive and one null: C.
The evidence, in fullNine papers, each linked to its PubMed record.
Razza et al. (Br J Psychiatry, 2026; PMID 41498282): individual patient data meta-analysis of 18 sham-controlled trials and 1,246 patients; Hedges' d 0.24, response odds ratio 1.33, remission not significant, with larger trials showing smaller differences. Positive trials: Brunoni et al. (JAMA Psychiatry, 2013; PMID 23389323), SELECT-TDCS, 120 patients in a factorial design with sertraline, tDCS alone better than placebo on MADRS; Brunoni et al. (N Engl J Med, 2017; PMID 28657871), ELECT-TDCS, 245 patients, tDCS beat placebo by 3.2 HDRS points but failed noninferiority to escitalopram, with more skin redness, tinnitus and nervousness and two cases of new-onset mania; Woodham et al. (Nat Med, 2025; PMID 39433921), 174 patients, 10 weeks of home-based tDCS with remote supervision, 2.3 HDRS points better than sham, funded in part by the device's maker. Null trials: Burkhardt et al. (Lancet, 2023; PMID 37414064), DepressionDC, 160 patients at eight German hospitals, triple-blind, tDCS added to an SSRI, no difference on MADRS at 6 weeks and more mild adverse events with active stimulation; Loo et al. (Brain Stimul, 2018; PMID 29111077), 130 patients in an international multisite trial, no difference from sham in unipolar or bipolar depression, with more remitters on sham in the unipolar group; Borrione et al. (JAMA Psychiatry, 2024; PMID 38170541), 210 patients, fully unsupervised home use with or without a digital intervention, no difference from sham, one nonfatal suicide attempt in the active arm. Ren et al. (JAMA Netw Open, 2025; PMID 40531534): meta-analysis of 88 trials; tDCS alone not significant in major depressive disorder, significant combined with medication. Li et al. (Pain Ther, 2026; PMID 42435147): network meta-analysis restricted to chronic musculoskeletal pain, where depressive symptoms were a secondary outcome; it does not test depression as a disorder and does not carry this grade. Grade C: positive pooled analyses alongside null multicenter trials is inconsistent evidence.
A clinician-rated depression scale (HAM-D or MADRS) at baseline and after the course, as the trials used. Electrode placement, current (mA), session duration and montage at every session.
Evidence notes: randomized trial, meta-analysis
Endpoint graded: Depressive symptoms in major depression on blinded clinician-rated scales (HAM-D, MADRS), mixed (clinician_rated)
Last reviewed: July 2026
Educational use only · Not medical advice · EBL grades published human evidence and does not recommend treatment. Stopping a prescription is a decision for your physician.
Primary evidenceNine papers, each linked to its PubMed record.
Razza et al. (Br J Psychiatry, 2026; PMID 41498282): individual patient data meta-analysis of 18 sham-controlled trials and 1,246 patients; Hedges' d 0.24, response odds ratio 1.33, remission not significant, with larger trials showing smaller differences. Positive trials: Brunoni et al. (JAMA Psychiatry, 2013; PMID 23389323), SELECT-TDCS, 120 patients in a factorial design with sertraline, tDCS alone better than placebo on MADRS; Brunoni et al. (N Engl J Med, 2017; PMID 28657871), ELECT-TDCS, 245 patients, tDCS beat placebo by 3.2 HDRS points but failed noninferiority to escitalopram, with more skin redness, tinnitus and nervousness and two cases of new-onset mania; Woodham et al. (Nat Med, 2025; PMID 39433921), 174 patients, 10 weeks of home-based tDCS with remote supervision, 2.3 HDRS points better than sham, funded in part by the device's maker. Null trials: Burkhardt et al. (Lancet, 2023; PMID 37414064), DepressionDC, 160 patients at eight German hospitals, triple-blind, tDCS added to an SSRI, no difference on MADRS at 6 weeks and more mild adverse events with active stimulation; Loo et al. (Brain Stimul, 2018; PMID 29111077), 130 patients in an international multisite trial, no difference from sham in unipolar or bipolar depression, with more remitters on sham in the unipolar group; Borrione et al. (JAMA Psychiatry, 2024; PMID 38170541), 210 patients, fully unsupervised home use with or without a digital intervention, no difference from sham, one nonfatal suicide attempt in the active arm. Ren et al. (JAMA Netw Open, 2025; PMID 40531534): meta-analysis of 88 trials; tDCS alone not significant in major depressive disorder, significant combined with medication. Li et al. (Pain Ther, 2026; PMID 42435147): network meta-analysis restricted to chronic musculoskeletal pain, where depressive symptoms were a secondary outcome; it does not test depression as a disorder and does not carry this grade. Grade C: positive pooled analyses alongside null multicenter trials is inconsistent evidence.
Products carry no letter. The letter belongs to the therapy as the trials studied it, and no trial tested these products unless the entry says so. Listed alphabetically; payment does not affect order.
tDCS + cognitive training app combination. CE-marked for depression treatment in Europe. Combined hardware + therapy protocol has the strongest evidence vs. device alone.
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