Validation and Optimal Cut-Off Score of the World Health Organization Well- being Index (WHO-5) as a Screening Tool for Depression among Patients with Schizophrenia

Background The utility of the World Health Organization Wellbeing Index (WHO-5) as rapid screening tool for depression has not yet been researched in the context of schizophrenia. The goal of this study was twofold: (1) examine the validity and reliability of the WHO-5 in schizophrenia; (2) estimate the optimal cut-off point for the WHO-5 to screen depression in this population. Methods Chronic, remitted patients with schizophrenia took part in this study. The Calgary Depression Scale for Schizophrenia was included as index of validity. Results The results of CFA supported the originally proposed unidimensional structure of the measure, with good internal consistency reliability (α = .80), concurrent validity, and cross-sex measurement invariance. The WHO-5 showed a sensitivity of 0.81 and a specificity of 0.70 in the detection of depression with a cut-off point of 9.5. The validity of the WHO-5 as a screening tool for depression was supported by the excellent discrimination AUC value of .838. Based on this WHO-5 cut-off value, 42.6% of the patients were screened as having a depression. Conclusion The study contributes to the field by showing that the WHO-5 is a concise and convenient self-report measure for quickly screening and monitoring depressive symptoms in patients with schizophrenia.