Overview and characteristics of included studies
| Study | Definition of partial remission of MDD | Mean baseline severity | Treatment group | Control group | Final FU (mo) | Outcome instruments | ||||
| Sample (n) | Mean age (SD) | Treatment received | Sample (n) | Mean age (SD) | Treatment received | |||||
| Paykel et al 28 | MDD (DSM-III-R) in last 18 mo, but not in last 2 mo (SADS); residual symptoms of ≥8 on HDRS-17 and ≥9 on BDI, for 2–18 mo | HDRS-17: 12.1 | 80 | 43.5 (9.8) |
CT: 16 individual sessions for 20 wk plus 2 booster sessions, 6 and 14 wk later. CM+ADM: CM every 4 wk and every 8 wk during FU, sessions 30 min each. CT or formal PT techniques prohibited. ADM usage: 100% Additional PT: 0% | 78 | 43.2 (11.2) |
ADMc only: every 4 wk during treatment and every 8 wk during FU, with CM sessions 30 min each. CT or formal PT techniques prohibited. ADM usage: 100% Additional PT: 0% | 72 | BDI; CID; SADS; HDRS-17 |
| Kennedy et al 36* | Showing partial response (HDRS-17 score 8–15) to 8–14 wk of open-label ADM; initially met DSM-IV criteria for MDE (SCID) | HDRS-17: 11.9 Previous MDE: 2.2 | 21 | 37.7 (11.3) |
LA: lithium carbonate augmentation of ADM for 8 wk. 600 mg/day prescribed, with clinicians permitted to increase dosing by 300 mg/day after 2–4 wk based on clinical response, tolerability and serum levels. Seen every 2 wk for CM. ADM usage: 100% | 23 | 40.7 (12.5) |
CT: 12 sessions CT over 8 wk. Emphasised acquisition and implementation of cognitive and behavioural skills. Medication check-up every 4 wk. ADM usage: 100% | 3 | BDI; HDRS-17 |
| Morgan et al 37* | MDD in partial remission (SCID); residual symptoms of 8–14 on HDRS-17; taking ADM for ≥8 wk | HDRS-17: 11.1 | 11 | 45.6 (3.2) | Oestrogen: conjugated oestrogen (0.625 mg/day) for 6 wk. New supply of medication at 2 wk intervals. ADM continued, prescribed by their primary treating physician. ADM usage: 100% | 6 | 47.2 (2.1) |
Placebo: placebo for 6 wk. New supply of medication at 2 wk intervals. ADM continued, prescribed by their primary treating physician. ADM usage: 100% | n/a | HDRS-17 |
| Holländare et al 39 | ≥1 MDE in last 5 yrs, no current MDE (SCID); treated with PT and/or ADM; residual symptoms of 7–19 on MADRS-S, ≥11 on BDI-II | HDRS-17: 10.76 Previous MDE: 5.96 | 42 | 44.8 (13.9) |
Internet-based CBT: 16 modules over 10 wk guided self-help CBT. Unrestricted email communication with a personal therapist. ADM usage: 43% Additional PT: 0% | 42 | 45.8 (11.9) |
TAU only: limited non-specific general support contact with therapist, for 10 wk. ADM usage: 57% Additional PT: 0% | 24 | BDI-II; MADRS-S; SCID-I |
| Watkins et al 41 | MDD (DSM-IV) in past 18 mo, but not in last 2 mo (SCID); residual symptoms of ≥8 on HDRS-17 and ≥9 on BDI-II; taking ADM for at least 8 wk continuously during the MDE and within the past 2 mo | HDRS-17: 12.74 Previous MDE: 5.14 | 21 | 43.05 (11.1) |
RF-CBT: 12 weekly/fortnightly individual sessions of manualised PT, for 60 min each. Helps individuals shift to constructive rumination, through functional analysis, experiential/imagery exercises and behavioural experiments. ADMc+CM: ADMc and outpatient CM, for 12 wk. Referred to as TAU. ADM usage: 100% Additional PT: 5% | 21 | 45.24 (9.35) |
ADMc only: ADM continuation and outpatient CM, for 12 wk. Referred to as TAU. ADM usage: 100% Additional PT: 33% | n/a | BDI-II; HDRS-17; SCID-I |
| Geschwind et al 43 | ≥1 previous MDE, but no current MDD (SCID); residual symptoms of HDRS-17 ≥7 | HDRS-17: 10.25 | 64 | 44.6 (9.7) |
MBCT: 8 weekly group sessions for 2.5 hours, with meditation, experiential exercises and discussions. Digital guided exercises and homework (30–60 min/day). TAU: usual treatment, if any, or waiting list, for 8 wk. ADM usage: 32% Additional PT: 12% | 66 | 43.2 (9.5) |
TAU only: continue usual treatment if any, or waiting list, for 8 wk. ADM usage: 38% Additional PT: 12% | 12 | HDRS-17; IDS; SCID-I |
| Schlögelhofer et al 40 | MDD in partial remission (DSM-IV-TR), based on the MINI); treated with adequate doses of ≥1 ADM before trial; residual symptoms of HDRS-17 10–19 | HDRS-17: 12.55 | 49 | 48.3 (10.9) |
Cognitive behavioural guided self-help: self-help book for depressive disorders, over 6 wk, guided by psychotherapist (2 sessions, 45 min each). ADMc: pharmacotherapy and CM by psychiatrist, over 6 wk. ADM usage: 100% Additional PT: 0% | 41 | 47.3 (13.2) |
ADMc only: pharmacotherapy and CM by psychiatrist, over 6 wk. ADM usage: 100% Additional PT: 0% | n/a | BDI; HDRS-17 |
| Teismann et al 42 | (Recurrent) partially remitted MDD (DSM-IV), based on the SCID; residual symptoms of BDI-II ≥9 | HDRS-17: 15.39 Previous MDE: 4.1 | 31 | 47.58 (11.3) |
RF-CBT: cognitive-behavioural small-group treatment for depressive rumination, in 11 weekly sessions for 90 min each. ADM usage: 38% Additional PT: 0% | 29 | 46.62 (12.47) |
TAU only: no treatment for 3 mo/no psychological treatment for 11 wk. Medication had to be stable; could include ADM. ADM usage: 31% Additional PT: 0% | 12 | BDI-II |
| Ionescu et al 38* | MDD in partial remission (SCID); ≥8 on HDRS-17; current treatment with ADM at a stable dose (≥4 wk) and duration (≥3 mo) | HDRS-28: 20.2† | 5 | – |
Iloperidone/Placebo order: Iloperidone of 1–8 mg, orally, once nightly for first 4 wk, followed by washout wk of single (patient)-blinded placebo and then 4 wk of placebo. Dosing regimen was fixed and allowed gradual titration. ADM usage: 100% | 8 | – |
Placebo/Iloperidone order: placebo for first 4 wk, followed by washout wk of single-blinded placebo and then 1–8 mg iloperidone, once nightly for 4 wk. Dosing regimen was fixed and allowed gradual titration. ADM usage: 100% | n/a | HDRS-28 |
| Segal et al 44 | ≥1 prior MDE (medical record diagnosis plus phone interview); residual symptoms of PHQ-9 score of 5–9 | HDRS-17: 12.23 Previous MDE: 7.46 | 230 | 48.3 (15.1) |
Mindful mood balance: MBCT-based intervention in online self-administered platform, minimal phone/email support (mean 2.34 hours), in 8 sessions over 12 wk. UDC: could include ADM, individual or group psychotherapy, or both, for period of 12 wk. ADM usage: 77% Additional PT: 51% | 230 | 48.2 (14.7) |
TAU only: referred to as UDC. Could include ADM, individual or group psychotherapy, or both, for period of 12 wk. ADM usage: 78% Additional PT: 50% | 15 | PHQ-9 |
*Trial only included in qualitative review and not meta-analysed.
†We were unable to transform HDRS-28 total scores to HDRS-17 total scores.
ADM, antidepressant medication; ADMc, antidepressant medication continuation; BDI, Beck Depression Inventory; CBT, cognitive behavioural therapy; CID, clinical interview for depression; CM, clinical management; CT, cognitive therapy; DSM-TR, Diagnostic and Statistical Manual of Mental Disorders, Text Revision; FU, follow-up; HDRS-17, 17 item Hamilton Depression Rating Scale; HDRS-28, 28 item Hamilton Depression Rating Scale; IDS, inventory of depressive symptoms; LA, lithium augmentation; MADRS-S, Montgomery Åsberg Depression Rating Scale-Self-rated; MBCT, mindfulness-based cognitive therapy; MDD, major depressive disorder; MDE, major depressive episode; MINI, Mini-International Neuropsychiatric Interview; mo, months; n/a, not applicable; PHQ-9, Patient Health Questionnaire-9; PT, psychotherapy; RF-CBT, rumination-focused cognitive behavioural therapy; SADS, Schedule for Affective Disorders and Schizophrenia; SCID, Structured Clinical Interview for the DSM; TAU, treatment as usual; UDC, usual depression care; wk, weeks; WL, waiting list.