Fourteen trials were included in the review (n=1,868): 12 randomised controlled trials (n=1,720) and two studies that were not randomised (n=148). Eleven studies were similar at baseline. All studies were equally treated except for intervention. Outcome assessment was blinded in five studies . All participants were accounted for at follow-up in 11 studies.
Effectiveness: The intervention had a positive effect in eight studies compared with control. Three trials reported significantly better depression symptom outcome scores in intervention groups compared with control. In eight trials, absolute risk reduction ranged from -17% to 45% (median 6%) and relative risk reduction ranged from -125% to 71% (median 33%).
Feasilbility: Enrolment rates ranged from 21% to 100% (median 45% to 49%);. Completion rates ranged from 53% to 100% (median 85%). Compliance rates ranged from 29% to 100% (median 80%). The author reported that heterogeneity in enrolment, completion and compliance could not be explained by characteristics of study populations or types of intervention.