Table 2

Characteristics of included systematic reviews

ReviewRisk of biasYears covered by searchesEligible study designsPopulationInterventionControlK relevant studies,
N analysed
Abbass 201440 LowNR to July 2012RCTsAdults, ≥18 years of age, with common mental disorders, allowed comorbid medical or psychiatric disorders (relevant study of African American women, 20–50 years of age, with depression)Psychodynamic therapies (short term)Inactive treatment
(waitlist)		Reduction: K=1, n=20
Al-Karawi 201645 MediumNR to December 2015RCTsPatients with non-seasonal depression diagnosed by standardised depression scalesBright light therapyInactive treatment (placebo device and pill-placebo)Reduction: K=1, n=62
Discontinuation (overall): K=1, n=62
Discontinuation (adverse events): K=1, n=62
Apaydin 201646 MediumJanuary 2007 to November 2014RCTsAdults, ≥18 years of age, with a diagnosis of MDDSt John’s wortInactive treatment
(pill-placebo)		Reduction: K=16, n=2888
Appleton 201532 LowAll years to May 2015 (except CINAHL, to September 2013)RCTs, cross-over and cluster RCTsAdults, ≥18 years of age, with a primary diagnosis of MDD or unipolar depressive disorder, allowed comorbid conditionsOmega-3 fatty acids (n-3PUFAs)Inactive treatment
(pill-placebo)		Reduction: K=6, n=308
Discontinuation (overall): K=7, n=446
Cujipers 201441 Medium1966 to January 2012RCTsAdults diagnosed with a depressive disorder, allowed comorbid medical or psychiatric disordersHumanistic therapy (supportive therapy)Inactive treatment
(pill-placebo)		Reduction: K=1, n=101
Integrative therapy (interpersonal therapy)Inactive treatment
(pill-placebo)		Reduction: K=1, n=33
Ekers 201439 High1966 to January 2013RCTsAdults, ≥16 years of age, with a primary diagnosis of depressionThird Wave CBT (behavioural activation therapy)Inactive treatment (waitlist, placebo)Reduction: K=9, n=338
Furukawa 201747 MediumNR to January 2015RCTsAdults with MDD, diagnosed according to DSM or ICD-10CBTInactive treatment
(pill-placebo)		Reduction: K=5, n=509
Galizia 201648 MediumNR to February 2016RCTsAdults, aged 18–80 years with a diagnosis of major depressionSAMeInactive treatment
(pill-placebo)		Reduction: K=2, n=142
Discontinuation (overall): K=2, n=142
Discontinuation (adverse events): K=1, n=124
Gartlehner 201544 MediumJanuary 1990 to September 2015RCTs, allowed non-randomised studies for harmsAdults, ≥19 years of age, with MDD during initial treatment attempt or second treatment attempt among those who did not achieve remission after treatment with an SGAAcupunctureSGAResponse: K=93 (NWMA), n=173
CBTSGAResponse: K=5, n=660
ExerciseSGAResponse: K=90 (NWMA), n=0
Integrative therapy (interpersonal psychotherapy)SGAResponse: K=1, n=318
Omega-3 fatty acidsSGAResponse: K=92 (NWMA), n=40
SAMeSGAResponse: K=90 (NWMA), n=0
St John’s wortSGAResponse: K=9, n=1517
Third Wave CBT (Behavioural activation)SGAResponse: K=2, n=243
SGAInactive treatment
(pill-placebo)		Reduction: K=62, n=13 759
Josefsson 201436 HighNR to April 2012RCTsAdults, ≥18 years of age, with depression or depressive symptomsExercise (aerobic or non-aerobic exercise, as monotherapy or with usual care, excluding eastern meditative practices)Inactive treatment
(no treatment, placebo)		Reduction: K=11, n=368
Jun 201434 MediumNR to February 2014RCTs, quasi-RCTsIndividuals of any age and either sex with depression, allowed comorbid diseasesGan Mai Da Zao
(decoction or modified decoction)		SGAResponse: K=3, n=148
Linde 201534 MediumNR to December 2013RCTsAdults with prevalent or incident unipolar depressive disorderSt John’s wortInactive treatment
(pill-placebo)		Discontinuation (overall): K=4, n=619
Discontinuation (adverse events): K=3, n=522
TCAInactive treatment
(pill-placebo)		Discontinuation (overall): K=4, n=484
Discontinuation (adverse events): K=3, n=421
SGAInactive treatment
(pill-placebo)		Discontinuation (overall): K=5, n=1195
Discontinuation (adverse events): K=6, n=1572
Liu 201537 HighNR to February 2014RCTsOlder adults, mean age ≥60 years, with depressive symptoms, and allowed comorbiditiesTai Chi, QigongInactive treatment (newspaper reading or reading and discussion group, health education)Reduction: K=3, n=193
Okumura, 201438 High1994 to June 2013RCTs, cluster RCTs, quasi-RCTsAdults, ≥18 years of age, with depression (elevated depressive symptoms, depressive disorders or minor depression), allowed comorbid physical illnessCBT (group CBT, mindfulness-based cognitive therapy)Inactive treatment
(waitlist, pill-placebo)		Discontinuation (overall): K=7, n=834
Sorbero 201533 MediumNR to January 2015RCTsAdults, ≥18 years of age, with a clinical diagnosis of MDD at enrolment or formerly depressed if primary outcome of study was depression relapse or recurrenceAcupuncture (specific, needle or electroacupuncture)Inactive treatment (non-specific acupuncture)Reduction: K=3, n=168
Taylor 201443 MediumNR to March 2013RCTsAdults with depressionAgomelatineInactive treatment
(pill-placebo)		Reduction: K=12, n=3855
Undurraga 201235 High1980 to August 2011RCTsAdults in an acute, apparently unipolar MDD episode or with ≤10% identified cases of bipolar depression or diagnoses other than MDDTCAInactive treatment
(pill-placebo)		Reduction: K=21, n=3094
Van Marwijk 201242 LowAll years to February 2012RCTsAdults, ≥18 years of age, with a primary diagnosis of MDD, a depressive episode, or if considered depressed and eligible for antidepressant treatment by a clinicianAlprazolamInactive treatment
(pill-placebo)		Reduction:
K=5, n=603
Yeung 201430 MediumNR to May 2013RCTs, quasi-RCTsIndividuals diagnosed with depressionChinese herbal medicineSGAResponse: K=5, n=1360
Inactive treatment
(pill-placebo)		Reduction: K=2, n=171
SaffronSGAResponse: K=1, n=38
Inactive treatment
(pill-placebo)		Reduction: K=2, n=80
Discontinuation (overall): K=2, n=80

  • CBT, cognitive behavioural therapy; K, number of studies that were eligible for review of reviews; MDD, major depressive disorder; N, number of participants in eligible studies; NR, not reported; NWMA, network meta-analysis; n-3PUFA, n-3 polyunsaturated fatty acid; RCT, randomised control trial; SGA, second-generation antidepressant; TCA, tricyclic antidepressants.