Validity and Reliability of an Adapted Persian Version of the Scoliosis Research Society-30 Questionnaire

Background: Adolescent idiopathic scoliosis (AIS) is a common type of spinal deformity confronting surgeons. The Scoliosis Research Society Health-Related Quality of Life (SRS-30) Questionnaire has been translated into Persian to evaluate its internal consistency, reliability, validity, and cross-cultural adaptability in the Persian population.

Methods: The translation and cultural adaptation process was based on the American Academy of Orthopaedic Surgeons guidelines. A total of 102 AIS patients referring to our institution were enrolled in this study within March 2014-March 2016. The 36-item Short Form (SF-36) was used for adapting the Persian SRS-30 questionnaire. The convergent validity of the Persian SRS-30 was examined using the Pearson correlation coefficient. Furthermore, its internal consistency and validity were tested using Cronbach α with bootstrapped 95% confidence interval. Interclass Correlation Coefficient (ICC) was used to test and retest reliability.

Results: The total correlation coefficient between the Persian SRS-30 and SF-36 was obtained at 0.74 (0.67-0.80), which was statistically significant (P=0.001). The total Cronbach α for the Persian SRS-30 was estimated at 0.84, ranging from 0.51 in satisfaction with management domains to 0.88 in mental health domains. The Persian SRS-30r domains indicated satisfactory test-retest reliability with ICC rage of 0.79-0.87.

Conclusion: The Persian SRS-30 translation was reliable and valid for the AIS Iranian patients. The internal consistency of this instrument was found to be good and excellent in all domains except satisfaction with management, which was moderate. The authors believe that the Persian version of SRS-30 is simple and easy to use and now it can be applied in clinical settings for future outcome studies in Iran.