Reliability and Validity of the Persian Version of the World Health Organization-Five Well-Being Index

Background: A multidimensional approach to health which addresses the psychological features of health justifies the necessity of designing or validation of brief instruments for screening in general population. This study aims to evaluate the reliability and validity of the Persian version of the WHO-5-P as a brief scale of well-being.Methods: In this study 451 individuals, i.e., over-15-year old subjects completed the WHO-5-P and GHQ-28 questionnaires. Crombach’s alpha and factor analysis were used for internal consistency evaluation. For predictive validity we compared WHO-5-P with GHQ-28 scores using receiver operating characteristic (ROC) analysis.Results: The mean age, score of WHO-5-P and GHQ-28 were 32.3±11.5, 13.4±6.5, and 25.4±13.4 respectively. The WHO-5-P had an acceptable internal consistency (α= 0.94), and it showed adequate convergent validity with the GHQ-28 (r= -0.66; P<0.001). The optimal cut-off score of the WHO-5-P was <13 (12.13) with a sensitivity of 0.68 and a specificity of 0.85. The area under curve in this study was 0.82. Confirmatory factor analysis revealed one factor structure.Conclusions: WHO-5-P is a valid and reliable instrument for screening psychological state