Psychometric Properties of the Overall Depression Severity and Impairment Scale and the Overall Anxiety Severity and Impairment Scale in an Indian Community Sample

Abstract

Anxiety and depressive disorders are global concerns that greatly add to disability-adjusted mortality, as well as social and economic burden. The Overall Anxiety Severity and Impairment Scale (OASIS) and the Overall Depression Severity and Impairment Scale (ODSIS) are valued for their brevity, applicability, and ease of use. However, their psychometric properties, including measurement invariance, remain unclear in India, where cultural and contextual factors may influence scale performance. The present cross-sectional psychometric study was conducted among 1204 participants aged 18 to 60 years (M = 24.78, SD = 7.61), of whom 71.6% were female. The findings support a unidimensional structure for both OASIS and ODSIS, with adequate factor loadings. Internal consistency was good to excellent (α = .902; ω = .904) for OASIS and (α = .899; ω = .899) for ODSIS, along with excellent test-retest validity. Additionally, both scales showed good convergent, divergent, discriminant, and predictive validity. These results indicate OASIS and ODSIS are reliable and valid instruments for assessing severity and functional impairment related to anxiety and depressive symptoms in an Indian community sample.