Cross-Cultural Adaptation and Psychometric Validation of the Hindi Version of the Neck Disability Index in Patients With Chronic Neck Pain.
Methods: Translation and psychometric testing. Objective: To cross-culturally adapt the Neck Disability Index (NDI) into the Hindi language, the local language of India, and to investigate the psychometric properties of the Neck Disability Index-Hindi (NDI-H) version in patients with neck pain.
Background: The NDI is the most used self-reported outcome measure for neck pain. The previous NDI-H version did not obtain advance permission from Mapi trust to translate this scale. As a result, this scale's availability is limited.
Methods: Following established guidelines, the NDI was translated and culturally adapted into Hindi. A total of 120 chronic neck pain patients (20 for cognitive interviews and 100 for psychometric testing) participated in this study. The content validity, construct validity, internal consistency, test-retest reliability, and responsiveness of the NDI-H were all evaluated. The intraclass correlation coefficient was computed to determine test-retest reliability. Internal consistency was assessed using Cronbach α. The NDI's factor structure was investigated using principal component factor analysis. The Neck Pain and Disability Scale, Numeric Pain Rating Scale, and Anxiety and Depression scales were used to test criterion validity. The receiver operating characteristic curve analysis was used to determine the cut-off point and the area under the curve.
Results: The NDI-H demonstrated good test-retest reliability (intraclass correlation coefficient = 0.92) and excellent internal consistency (Cronbach α = 0.90). The one-factor structure was revealed by the factor analysis. The NDI has a strong relationship with the Neck Pain and Disability Scale and Numeric Pain Rating Scale, as well as the Anxiety and Depression scales. The cut-point for detecting a change was 9.3.
Conclusions: The NDI was successfully translated into Hindi in this study. The NDI-H is a reliable and valid and responsive instrument that can be used to treat patients with chronic neck pain in clinical and research settings.