Cross-cultural Adaptation and Validation of the Nepali Translation of the Patient-Specific Functional Scale.

Background The Patient-Specific Functional Scale (PSFS) is among the most commonly used measures to assess physical function. Objectives We aimed to translate and cross-culturally validate the PSFS to Nepali and further assess its psychometric properties. 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. 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<.001), and numeric pain-rating scale (r = -0.32 and -0.55, P<.001). Areas under the curve ranged from 0.72 to 0.99. The MIC was 2.00 in the main analysis. Secondary analyses revealed MICs of 0.50, 0.66, and 2.00 for small, medium, and large improvement, respectively. Conclusion The PSFS-NP is a reliable, valid, and responsive measure. It can be used in clinical practice and research in Nepalese with musculoskeletal pain. J Orthop Sports Phys Ther 2018;48(8):659-664. Epub 6 Apr 2018. doi:10.2519/jospt.2018.7925.

Translation, cross-cultural adaptation and psychometric properties of the Nepali versions of numerical pain rating scale and global rating of change.

BACKGROUND: Pain intensity and patients' impression of global improvement are widely used patient-reported outcome measures (PROMs) in clinical practice and research. They are commonly assessed using the Numerical Pain Rating Scale (NPRS) and Global Rating of Change (GROC) questionnaires. The GROC is essential as an anchor for evaluating the psychometric properties of PROMs. Both of these PROMs are translated to many languages and have shown excellent psychometric properties. Their availability in Nepali would facilitate pain research and cross-cultural comparison of research findings. Therefore, the objectives of this study were to translate and cross-culturally adapt the NPRS and GROC into Nepali and to assess the psychometric properties of the Nepali version of the NPRS (NPRS-NP). METHODS: After translating and cross-culturally adapting the NPRS and GROC into Nepali using recommended guidelines, NPRS-NP was administered to 104 individuals with musculoskeletal pain twice. The Nepali version of the GROC (GROC-NP) was administered at the follow-up for anchor-based assessment. (1) Test-retest reliability and minimum detectable change (MDC) among the stable group, (2) construct validity (by single sample t-test within the improved group and independent sample t-test between groups), and (3) concurrent validity were assessed. Receiver operating characteristic (ROC) curves were plotted to determine the responsiveness of the NPRS-NP using the area under the curve (AUC), and minimum important changes (MIC) for small, medium and large improvements. RESULTS: Significant cultural adaptations were required to obtain relevant Nepali versions of both the NPRS and GROC. The NPRS-NP showed excellent test-retest reliability and a MDC of 1.13 points. NPRS-NP demonstrated a good construct validity by significant within-group difference in mean of NPRS score- t(63)= 7.57, P < 0.001 and statistically significant difference of mean score- t(98)= -4.24, P < .001 between the stable and improved groups. It demonstrated moderate concurrent correlation with the GROC-NP; r = 0.43, P < 0.01. Responsiveness of the NPRS-NP was shown at three levels with AUC = 0.68-0.82, and MIC = 1.17-1.33. CONCLUSIONS: The NPRS and GROC were successfully translated and culturally adapted into Nepali. The NPRS-NP demonstrated good reliability, validity and responsiveness in assessing musculoskeletal pain intensity in a Nepali population.