Translation, Cross-Cultural Adaptation, Reliability, and Validity of the Persian Version of the Neck Outcome Score Questionnaire in Iranian Patients With Nonspecific Neck Pain

Abstract

ObjectiveThe primary purpose of this study was to translate and culturally adapt the neck outcome score (NOOS) questionnaire into Persian language and investigate its reliability and validity. MethodsThe NOOS questionnaire was translated into Persian language and culturally adapted according to American Academy of Orthopaedic Surgeons guidelines. One hundred four patients with nonspecific neck pain were requested to complete the Persian version of the NOOS questionnaire, 36-item short form survey (SF-36), and neck disability index (NDI) questionnaire. The 95 patients of them were requested to fulfill the Persian version of NOOS again, with 3 to 5 days interval. The internal consistency and test-retest reliability were assessed using Cronbach's α and intraclass correlation coefficient, respectively. The construct validity was assessed by testing the hypothesis of correlations between NOOS subscales, SF-36 subscales, and NDI, and pain was measured using visual analog scale. ResultsOne hundred four patients with nonspecific neck pain participated in validity studies and 95 patients agreed to participate in reliability studies. Floor/ceiling effects were not observed. Cronbach's α values of the subscale ranged between 0.60 and 0.89. The intraclass correlation coefficient measures of the NOOS subscales ranging between 0.81 and 0.95. The correlation coefficient between NOOS subscales and SF-36 subscales ranged between 0.11 and 0.72. The correlation coefficient between NOOS subscale scores and NDI questionnaire ranged between 0.33 and 0.61. The correlation coefficient between NOOS subscale scores, and pain (visual analog scale) ranged between 0.31 and 0.66. ConclusionThis study showed that the Persian version of the NOOS questionnaire was a reliable and valid instrument to assess patients’ perception of their neck-related problems in Iranian patients with nonspecific neck pain.