Group psychological therapies for depression in the community: systematic review and meta-analysis

Background Psychological therapies have been shown to be effective in the treatment of depression. However, evidence is focused on individually delivered therapies, with less evidence for group-based therapies. Aims To conduct a systematic review and meta-analysis of the efficacy of group-based psychological therapies for depression in primary care and the community. Method We searched MEDLINE, Embase, PsycINFO, the Cochrane Central Register of Controlled Trials and the Cochrane Collaboration Depression, Anxiety and Neurosis Review Group database from inception to July 2010. The Cochrane risk of bias methodology was applied. Results Twenty-three studies were included. The majority showed considerable risk of bias. Analysis of group cognitive-behavioural therapy (CBT) v. usual care alone (14 studies) showed a significant effect in favour of group CBT immediately post-treatment (standardised mean difference (SMD) -0.55 (95% CI -0.78 to -0.32)). There was some evidence of benefit being maintained at short-term (SMD= -0.47 (95% CI -1.06 to 0.12)) and medium- to long-term follow-up (SMD= -0.47 (95% CI - 0.87 to -0.08)). Studies of group CBT v. individually delivered CBT therapy (7 studies) showed a moderate treatment effect in favour of individually delivered CBT immediately post-treatment (SMD=0.38 (95% CI 0.09-0.66)) but no evidence of difference at short- or medium- to long-term follow-up. Four studies described comparisons for three other types of group psychological therapies. Conclusions Group CBT confers benefit for individuals who are clinically depressed over that of usual care alone. Individually delivered CBT is more effective than group CBT immediately following treatment but after 3 months there is no evidence of difference. The quality of evidence is poor. Evidence about group psychological therapies not based on CBT is particularly limited.