Effectiveness of psychological and/or educational interventions to prevent the onset of episodes of depression: A systematic review of systematic reviews and meta-analyses

•Psychological and/or educational interventions are effective in preventing depression.•The effect size of these interventions is small or moderate.•Only 24% of trials had follow-up > 12 months; their effectiveness is questionable.•Randomized controlled trials with longer follow-up and large samples are needed.

ObjectiveTo determine the effectiveness of psychological and/or educational interventions to prevent the onset of episodes of depression.MethodsSystematic review of systematic reviews and meta-analyses (SR/MA). We searched PubMed, PsycINFO, Cochrane Database of Systematic Reviews, OpenGrey, and PROSPERO from their inception until February 2014. Two reviewers independently evaluated the eligibility criteria of all SR/MA, abstracted data, and determined bias risk (AMSTAR).ResultsTwelve SR/MA (156 non-repeated trials and 56,158 participants) were included. Of these, 142 (91%) were randomized-controlled, 13 (8.3%) controlled trials, and 1 (0.6%) had no control group. Five SR/MA focused on children and adolescents, four on specific populations (women after childbirth, of low socioeconomic status, or unfavorable circumstances; patients with severe traumatic physical injuries or stroke) and three addressed the general population. Nine (75%) SR/MA concluded that interventions to prevent depression were effective. Of the 156 trials, 137 (87.8%) reported some kind of effect size calculation. Effect sizes were small in 45 (32.8%), medium in 26 (19.1%), and large in 25 (18.2%) trials; 41 (29.9%) trials were not effective. Of the 141 trials for which follow-up periods were available, only 34 (24.1%) exceeded 12 months.ConclusionPsychological and/or educational interventions to prevent onset of episodes of depression were effective, although most had small or medium effect sizes.