Validation of the Italian spine youth quality of life (ISYQOL) in Korean population.

ABSTRACT

We aimed to evaluate the reliability and validity of the adapted Korean version of the Italian Spine Youth Quality of Life (ISYQOL) questionnaire. Translation/retranslation of the English version of ISYQOL was conducted, and all steps of the cross-cultural adaptation process were performed. The Korean version of the ISYQOL and the previously validated Scoliosis Research Society-22 (SRS-22) questionnaire were mailed to 120 consecutive idiopathic scoliosis patients wearing brace. Factor analysis and reliability assessment by kappa statistics of agreement for each item, the intraclass correlation coefficient (ICC) and Cronbach's α were conducted. Construct validity was also evaluated by comparing the responses of ISYQOL with the responses of SRS-22 by using Pearson's correlation coefficient. Factor analysis extracted 2 factors. All items had a kappa statistics of agreement greater than 0.6. The ISYQOL showed good test/re-test reliability (ICC = 0.812). Internal consistency of Cronbach's α was found to be very good (α = 0.873). The Korean version of ISYQOL showed good significant correlation with SRS-22 total score and with single SRS-22 domains scores. The adapted Korean version of the ISYQOL was successfully translated and showed acceptable measurement properties, and as such, is considered suitable for outcome assessments in the Korean speaking patients with idiopathic scoliosis.