Reliability and concurrent validity of the adapted Chinese version of Scoliosis Research Society-22 (SRS-22) questionnaire

Study Design. Validation study to define validity and reliability of an adapted and translated questionnaire. Objective. Assessment of the concurrent validity and reliability of a Chinese version of SRS-22 outcome instrument. Summary of Background Data. No valid health-related quality of life (HRQL) outcome instrument exists for patients with spinal deformity in Chinese. The modified SRS-22 questionnaire was proven to be an appropriate outcome instrument in English, and has already been translated and validated in several other languages. Methods. The English version of the SRS-22 questionnaire was adapted to Chinese according to the International Quality of Life Assessment Project guidelines. To assess reliability, 48 subjects with adolescent idiopathic scoliosis ( mean age, 16.5 years) filled the questionnaire on 2 separate occasions ( Group 1). To assess concurrent validity, 50 subjects ( mean age, 21 years) filled in the same questionnaire and a previously validated Chinese version of the Short Form-36 (SF36) questionnaire ( Group 2). Internal consistency, reproducibility and concurrent validity were determined with Cronbach's alpha coefficient, interclass correlation coefficient and Pearson correlation coefficient, respectively. Results. Cronbach's alpha coefficient for the 4 major domains (function/activity, pain, self-image/appearance and mental health) were high. Intraclass correlation was also excellent for all domains. For concurrent validity, excellent correlation was found in 1 domain, good in 12 domains, moderate in 3 domains, and poor in 1 domain of the 17 relevant domains. Discussion. Both cultural adaptation and linguistic translation are essential in any attempt to use a HRQL questionnaire across cultures. The Chinese version of the SRS-22 outcome instrument has satisfactory internal consistency and excellent reproducibility. It is ready for use in clinical studies on idiopathic scoliosis in Chinese-speaking societies.