Concordance among the patient-, proxy-, and clinician-rated versions of World Health Organization Disability Assessment Schedule-2.0 36-item version in India

Background: The World Health Organization Disability Assessment Schedule-2.0 (WHODAS 2.0) is a disability assessment instrument which is based on the conceptual framework of the International Classification of Functioning, Disability, and Health. It provides a global measure of disability and it has seven domains-specific scores. Objective: The present study aims to check the concordance among the patient, proxy, and clinician-rated versions of WHODAS 2.0 in India. Materials and Methods: This study was cross-sectional and comparative in nature. Sixty samples of patients with severe mental illness (SMI) were selected using a consecutive sampling procedure as per the International Classification of Diseases (ICD-10) criteria. Using patient, proxy, and clinician administrative version of WHODAS 2.0, the study was conducted at the outpatient department of Mental Health Institute and Department of Psychiatry, Government Medical College and Hospital Sector 32, Chandigarh, India. Patients diagnosed with SMI as per the ICD-10 aged above 18 years of age with a total duration of illness of at least more than 2 years were included. Those who refused to participate were excluded. The data were analyzed using the SPSS software. The normality of quantitative data was checked by the measures of Kolmogorov–Smirnov tests of normality. The continuous data were reported as mean ± standard deviation. The categorical variables were reported as counts and percentages. The group comparisons were made with the help of ANOVA test. Results: This study included 60 patients with SMI, and the results show that there was no significant difference found among the patient, proxy, and clinician's assessment for most items, but the mean score of the clinician-rated version score (68.733) was higher in comparison to patient- and proxy-rated versions of WHODAS 2.0. Conclusion: The overall inter-reliability of WHODAS 2.0 among the patients, proxy, and clinician was moderate. There was no significant difference among the patient, proxy, and clinician's assessments for most items. This highlights the fact that one does not have to rely on professionals' ratings for assessing the disability among patients with SMI.