Premium
Does psychotherapy work? An umbrella review of meta‐analyses of randomized controlled trials
Author(s) -
Dragioti E.,
Karathanos V.,
Gerdle B.,
Evangelou E.
Publication year - 2017
Publication title -
acta psychiatrica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.849
H-Index - 146
eISSN - 1600-0447
pISSN - 0001-690X
DOI - 10.1111/acps.12713
Subject(s) - meta analysis , psycinfo , randomized controlled trial , systematic review , random effects model , medline , psychology , psychotherapist , clinical psychology , medicine , political science , law
Objective To map and evaluate the evidence across meta‐analyses of randomized controlled trials ( RCT s) of psychotherapies for various outcomes. Methods We identified 173 eligible studies, including 247 meta‐analyses that synthesized data from 5157 RCT s via a systematic search from inception to December 2016 in the PubMed, Psyc INFO and Cochrane Database of Systematic Reviews. We calculated summary effects using random‐effects models, and we assessed between‐study heterogeneity. We estimated whether large studies had significantly more conservative results compared to smaller studies (small‐study effects) and whether the observed positive studies were more than expected by chance. Finally, we assessed the credibility of the evidence using several criteria. Results One hundred and ninety‐nine meta‐analyses were significant at P ‐value ≤ 0.05, and almost all ( n = 196) favoured psychotherapy. Large and very large heterogeneity was observed in 130 meta‐analyses. Evidence for small‐study effects was found in 72 meta‐analyses, while 95 had evidence of excess of significant findings. Only 16 (7%) provided convincing evidence that psychotherapy is effective. These pertained to cognitive behavioural therapy ( n = 6), meditation therapy ( n = 1), cognitive remediation ( n = 1), counselling ( n = 1) and mixed types of psychotherapies ( n = 7). Conclusions Although almost 80% meta‐analyses reported a nominally statistically significant finding favouring psychotherapy, only a few meta‐analyses provided convincing evidence without biases.