A Cochrane review [Abstract] 1 included 12 studies with a total of 5 693 subjects. The most commonly used instruments were self-completed scales designed to detect depression, e.g. Beck Depression Inventory (BDI), General Health Questionnaire (GHQ), or Zung SDI.
Screening/case finding instruments had borderline impact on the overall recognition of depression by clinicians (relative risk 1.38; 95% confidence interval 1.04 to 1.83; 9 trials, n=4 194). Studies showed substantial heterogeneity, and publication bias was also found. Screening with unselected feedback had no impact on the detection of depression (RR 1.00; 95% CI 0.89 to 1.13). A two stage procedure with screening and selective feedback of positive results for those who score above a certain threshold might be an effective approach (RR 2.66; 95% CI 1.78 to 3.96).
Concerning the management of depression, there was an overall trend showing a borderline higher intervention rate amongst those who received feedback of screening/case finding instruments (RR 1.35; 95% CI 0.98 to 1.85; 8 trials, n=2 272). Substantial heterogeneity existed between studies and the result was dependent on one highly positive study. Three out of four studies reporting on the actual outcome of depression showed no clinical effect (p<0.05) at either six months or twelve months.
Comment: The quality of evidence is downgraded by inconsistency (variability in results across studies).
Primary/Secondary Keywords