Reliability and validity of the adapted Turkish version of the Spinal Appearance Questionnaire

Spine Deform. 2020 Aug 17. doi: 10.1007/s43390-020-00193-3. Online ahead of print.

Abstract

Purpose: The Spinal Appearance Questionnaire (SAQ), scoliosis specific quality of life questionnaire, was developed to assess the spinal appearance in adolescent idiopathic scoliosis (AIS) patients. The aim of this study is to evaluate the adaptation, validity, and reliability of the Turkish version of the Spinal Appearance Questionnaire (Tr-SAQ).

Methods: Tr-SAQ and already validated Turkish SRS-22 were applied to 75AIS patients (56 females) twice within a 2-week interval for test-retest reliability. Validity of the Tr-SAQ was assessed with factor analysis, convergent validity, and discriminant validity. Convergent validity was evaluated by calculating Spearman correlation coefficients between Tr-SAQ and SRS-22 self-image domain. Internal consistency and intraclass correlation coefficient (ICC) were evaluated for the determination of reliability.

Results: Factor analysis indicated that Tr-SAQ had two factors as appearance (items 1-10) and expectations (items 12-15). Convergent validity test showed a significant negative correlation between the Tr-SAQ appearance score and SRS-22 self-image score (Spearman's r = - 0.6).Test-retest was conducted within a mean of 16.7 (range 14-28) days. Both ICC and Cronbach's α were found to be high (0.98, 0. 91, respectively). The correlations with the major curve magnitude were stronger for the Tr-SAQ Appearance (r = 0.7) and Tr-SAQ Total (r = 0.6) scores than the correlations between the SRS-22 self-image (r = - 0.5) and SRS-22 Total (r = - 0.4) scores.

Conclusion: The Turkish version of the SAQ was reliable and valid for clinical use for AIS patients who are native speakers of Turkish.

Level of evidence: Level I- diagnostic studies.

Keywords: Adolescent idiopathic scoliosis; Cross-cultural adaptation; Spinal appearance questionnaire; Validation.