Validity of the self-rated 36-item World Health Organization Disability Assessment Schedule (WHODAS) 2.0 as a measure of functioning in Swedish psychiatric outpatients.

The aim of this study was to investigate concurrent validity of the Swedish self-rated 36-item World Health Organization Disability Assessment Schedule (WHODAS) 2.0 by comparison with professional Global Assessment of Functioning (GAF) ratings in psychiatric outpatients. A cross-sectional convenience sample of 444 patients was recruited from their regular psychiatric outpatient settings. The patients filled out the WHODAS 2.0; their clinicians provided clinical information and performed GAF ratings blinded to the patients' assessments. Analyses of correlations, variance components, and ROC curves were performed to investigate the validity of the WHODAS 2.0 through comparison with the GAF. The variance component analyses included working status, psychosocial problems, number of diagnostic groups, and remission status. GAF ratings were separated as total (GAF-T), symptoms (GAF-S), and functioning (GAF-F). There was significant correlation ( Concurrent validity was found when comparing the Swedish self-administered 36-item version of WHODAS 2.0 with the expert-rated GAF in psychiatric outpatients.