Validation and comparison of diagnostic accuracy of four screening tools for mental disorders in people seeking treatment for substance use disorders.

This study aimed to validate and compare performance of four screening tools for mental disorders in a heterogeneous population seeking substance use treatment. A total of 544 clients were recruited prospectively from three treatment centres and completed the screening instruments followed by a reference standard psychiatric interview for research diagnosis. Performance relative to the reference standard was compared across instruments using receiver operator characteristic (ROC) analysis. Screening tools included the GAIN-SS-IDScr; the K6, the Psychiatric Sub-scale of the Addiction Severity Index, and the Psychiatric Diagnostic Screening Questionnaire. All the screening tools performed reasonably well detecting broad groupings of disorders-any past-month disorder, any depressive disorder, anxiety disorder or psychotic disorder, with the GAIN-SS-IDScr being most efficient due to its shorter length. Results strengthen previous validation data for each of the tools investigated and support their use in detecting mental disorders in the substance use treatment population specifically.