Objective Although practice guidelines for depression screening are evidence based, with their development relying on reviews of controlled studies, their adaptation and use as quality indicators have not been subject to rigorous study. This paper will therefore review the evidence supporting this practice.Methods A rational evaluation was carried out on both controlled studies and other sources of evidence related to the technical, clinical and policy assumptions underlying the use of depression screening guidelines as quality indicators.Results 1) Technical assumptions: depression screening could be used as a quality indicator. Current information technology does not allow accurate determination of who would benefit from being screened, whether they actually were screened, or the optimal percentage that should be screened. 2) Clinical assumptions: depression screening would improve outcomes. The evidence suggests that although depression screening might increase the diagnosis of depression, depressed patients so recognised tend to be less ill, less in need of treatment, or less likely to benefit from treatment, while screening, in the absence of other interventions, does not improve outcomes. 3) Policy assumptions: depression screening should be a focus of quality improvement. However, relative to other preventative measures, depression screening is a low priority. It does not meet usual cost-effectiveness criteria. There are more robust interventions for depression (i.e. collaborative care) that could be a focus of quality improvement efforts.Conclusion Although routine depression screening may be an acceptable practice guideline, its use as a quality measure is not supported.