The Cross-Cultural Adaptation, Reliability, and Validity of the Copenhagen Neck Functional Disability Scale in Patients With Chronic Neck Pain Turkish Version Study

Study Design. The study design was cross-cultural adaptation and investigation of reliability and validity of the Copenhagen Neck Functional Disability Scale (CNFDS). Objective. The aim of this study was to translate the CNFDS into Turkish language and assess its reliability and validity among patients with neck pain in Turkish population. Summary of Background Data. The CNFDS is a reliable and valid evaluation instrument for disability, but there is no published the Turkish version of the CNFDS. Methods. One hundred one subjects who had chronic neck pain were included in this study. The CNFDS, Neck Pain and Disability Scale, and visual analogue scale were administered to all subjects. Results. For investigating test-retest reliability, correlation between CNFDS scores, applied at 1-week interval, intraclass correlation coefficient score for test-retest reliability was 0.86 (95% confidence interval = 0.679-0.935). There was no difference between test-retest scores (P < 0.001). For investigating concurrent validity, correlation between total score of the CNFDS and the mean visual analogue scale was r = 0.73 (P < 0.001). Concurrent validity of the CNFDS was very good. For investigating construct validity, correlation between total score of the CNFDS and the Neck Pain and Disability Scale was r = 0.78 (P < 0.001). Construct validity of the CNFDS was also very good. Conclusion. Our results suggest that the Turkish version of the CNFDS is a reliable and valid instrument for Turkish people.