Screening and case-finding instruments for depression: a meta-analysis

BACKGROUND: Screening and case-finding has been proposed as a simple, quick and cheap method to improve the quality of care for depression. We sought to establish the effectiveness of screening in improving the recognition of depression, the management of depression and the outcomes of patients with depression. METHODS: We performed a Cochrane systematic review of randomized controlled trials conducted in nonmental health settings that included case-finding or screening instruments for depression. We conducted a meta-analysis and explored heterogeneity using meta-regression techniques. RESULTS: Sixteen studies with 7576 patients met our inclusion criteria. We found that the use of screening or case-finding instruments were associated with a modest increase in the recognition of depression by clinicians (relative risk RR 1.27, 95% confidence interval CI 1.02 to 1.59). Questionnaires, when administered to all patients and the results given to clinicians irrespective of baseline score, had no impact on recognition (RR 1.03, 95% CI 0.85 to 1.24). Screening or case finding increased the use of any intervention by a relative risk of 1.30 (95% CI 0.97 to 1.76). There was no evidence of influence on the prescription of antidepressant medications (RR 1.20, 95% CI 0.87 to 1.66). Seven studies provided data on outcomes of depression, and no evidence of an effect was found (standardized mean difference -0.02, 95% CI -0.25 to 0.20). INTERPRETATION: If used alone, case-finding or screening questionnaires for depression appear to have little or no impact on the detection and management of depression by clinicians. Recommendations to adopt screening strategies using standardized questionnaires without organizational enhancements are not justified.