Validation and reliability of the Persian version of the Zurich Claudication Questionnaire in patients with lumbar spinal stenosis

BACKGROUND: One of the applicable tools introduced as a specific tool for assessing claudication in patients with lumbar spinal stenosis is the Zurich Claudication Questionnaire (ZCQ). This questionnaire has been validated in different populations of patients. The present study aimed to determine the validation status of the Persian version of ZCQ. METHODS: After professional translation of the ZCQ by native English translators, it was executed twice before surgery with 1 day interval on 45 Iranian patients with spinal stenosis. The reliability was assessed by determining the Chronbach's Alpha coefficient as well as intraclass correlation coefficient (ICC). To assess the concurrent validity, the correlation across the 3 domains of the questionnaire was calculated by the Pearson's correlation test and the content validity was determined using a panel of experts. RESULTS: To assess test-retest reliability, the ICC for ZCQ for symptom severity, functional disability, and satisfaction domains were 0.80, 0.82, and 0.78, indicating acceptable reliability. Regarding internal consistency, Cronbach's alpha coefficients for the Persian version of ZCQ for the 3 above domains were shown to be 0.96, 0.92, and 0.90 respectively. On the subject of content validity, the 3 questionnaire's domains were marked as relevant with the content validity indices of 0.88, 0.82, and 0.80 respectively. Concerning concurrent validity, all 3 domains of the Persian ZCQ correlated strongly with 1 another. CONCLUSIONS: The ZCQ questionnaire with the same original structure is completely functional and reliable in the Iranian patient community.