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

Abstract

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.