The Italian Spine Youth Quality of Life questionnaire: reliability and validity of the Persian version in adolescents with spinal deformities

Purpose To assess the reliability and validity of the Persian version of the Italian Spine Youth Quality of Life (P-ISYQOL) questionnaire. Methods Forward/backward translations and cultural adaption processes of the ISYQOL questionnaire into Persian were conducted by an expert committee. We recruited 178 adolescents with idiopathic scoliosis (AIS) and Scheuermann’s kyphosis (SK) and 103 age-matched adolescents with no spinal deformity. Reliability was assessed by evaluating internal consistency and test–retest reliability using Cronbach’s alpha and intraclass correlation coefficient (ICC). Convergent construct validity was assessed by measuring the association between the ISYQOL and revised 22-item Scoliosis Research Society (SRS-22r) questionnaires scores. Known-groups construct validity was assessed regarding curve magnitude, deformity, age, sex, and treatment type. Results Cronbach’s alpha and ICC for P-ISYQOL total score was 0.8 and 0.9, respectively. An acceptable association was observed between P-ISYQOL and SRS-22r total scores ( r = − 0.5, p < 0.01). The P-ISYQOL could discriminate between adolescents with spinal deformities and adolescents with no spinal deformity as well as those with different types of deformity and treatment ( p < 0.01). Conclusions The P-ISYQOL is a reliable and valid survey to assess the outcomes of adolescents with spinal deformities. Level of evidence Level I—diagnostic studies.