Cross-cultural adaptation and validation of the Nepali translation of the patient-specific functional scale

Abstract

BACKGROUND: The Patient-Specific Functional Scale (PSFS) is among the most commonly used measures to assess physical function. U OBJECTIVES: We aimed to translate and cross-culturally validate the PSFS to Nepali and further assess its psychometric properties. U METHODS: This longitudinal, single-arm cohort study translated and cross-culturally adapted the PSFS to Nepali (PSFS-NP) following recommended guidelines. A sample of 104 Nepalese with musculoskeletal pain was recruited to evaluate the psychometric properties of the PSFS-NP. We assessed the internal consistency (Cronbach alpha), 2-week test-retest reliability (intraclass correlation coefficient [ICC3,2]), the smallest detectable change at the 90% confidence interval (CI), and construct validity. Concurrent validity was assessed against the Nepali versions of the Oswestry Disability Index, global rating of change, and numeric pain-rating scale. Receiver operating characteristic curves were plotted to measure responsiveness and area under the curve, and the minimum important change (MIC) was estimated. U RESULTS: The PSFS-NP showed good reliability, with a Cronbach alpha of .75, an ICC of 0.89 (95% CI: 0.78, 0.94), and a smallest detectable change at the 90% CI of 1.46. It demonstrated significant correlations with the Nepali versions of the Oswestry Disability Index (r = -0.47, P = .001), global rating of change (r = 0.71, P