This review found that some types of brief psychosocial interventions had potential to prevent depression in older people. The reliability of the author's conclusions is unclear due to poor reporting of the review process and the possibility of publication and language biases.

To investigate the effectiveness and feasibility of brief interventions to prevent depression in older people.

MEDLINE, PsycINFO, EMBASE and HealthStar were searched for studies published in English or French (dates spanned January 1966 to August 2007); search terms were reported. Bibliographies were searched.

Controlled trials of a brief intervention (<12 weeks) to prevent depression in which participant mean age was at least 40 years and depression status was determined six months or more after enrolment were eligible for inclusion. An acceptable definition of depression had to be used (no further details reported).

The included studies were of brief psychosocial interventions; most were selective preventative interventions and some were trials of indicated interventions. Mean age of participants ranged from 41 to 80 years. Intervention duration ranged from six to 12 weeks, where reported. Various measures of depression were used in the included studies. Populations were recruited from a wide range of settings.

The author did not state how many reviewers selected studies for inclusion.

Methodological quality was assessed in terms of criteria described by the Evidence-Based Working Group (randomisation, similarity at baseline, groups equally treated except for intervention, blinding of outcome assessment and completeness of follow-up).

The author did not state how many reviewers assessed study quality.

Enrolment rates, completion rates and compliance rates were extracted to examine feasibility. For effectiveness, differences in depression symptom outcome scores or (when available) absolute risk reduction and relative risk reduction were extracted.

The number of reviewers who extracted data was not reported.

The results were synthesised narratively. Individual study details were presented in tables.

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.

Some types of brief psychosocial intreventions had potential to prevent depression in older people.

The inclusion criteria were defined in terms of participants, intervention and study design. Four relevant databases were searched. Only studies published English or French were included, so language and publication biases could not be ruled out. The author did not report how review processes were performed, so any steps taken to reduce error and bias were unknown. Study quality was assessed and taken into consideration. Narrative synthesis appeared appropriate given the differences in outcomes, interventions and populations.

The reliability of the author's conclusions is unclear due to poor reporting of the review process and the possibility of publication and language biases.

Practice: The author did not state any recommendations for practice.

Research: The author made 14 recommendations for future research (described in the report).

Not stated.

Cole MG, Dendukuri N. The feasibility and effectiveness of brief interventions to prevent depression in older subjects: a systematic review. International Journal of Geriatric Psychiatry 2004; 19(11): 1019-1025

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.