THE GREEK VERSION OF THE SPINAL APPEARANCE QUESTIONNAIRE (SAQ) IN PATIENTS WITH ADOLESCENT IDIOPATHIC SCOLIOSIS: VALIDITY, RELIABILITY AND PSYCHOMETRIC MEASURES

M. Economaki^1,2, A. Georgios¹, G. Kelalis³, S. Sotiropoulos^1,2, G. Georgoudis^1,2

Background: The SAQ has been created to assess the perception of body image and spinal deformity in Adolescent Idiopathic Scoliosis. The initial study and all eight cultural adaptations have shown its validity, reliability and responsiveness. However, there is no published Greek version of the SAQ until today.

Purpose: The aim of this study was to develop a valid, reliable and psychometrically sound Greek version of the Spinal Appearance Questionnaire (GR-SAQ).

Methods: The cross-cultural validation and adaptation of the SAQ was performed according to the international guidelines. A sample of 33 AIS patients was employed. The internal consistency using Cronbach’s α and the test-retest reliability using the Intraclass Correlation Coefficient (ICC) were examined with 5-7 days apart. The GR-SAQ and the domain “Appearance” of the already validated into Greek of the Scoliosis Research Society-22 (GR-SRS-22) tools were correlated in order to assess for convergent validity. The Cobb angle and the “Trunk shift” domain of the GR-SAQ (questions 4,5) were compared in order to further evaluate the convergent validity of GR-SAQ. Divergent validity was demonstrated by the analysis of the relationship between the GR-SAQ “Kyphosis” domain with the Cobb Angle, the Angle from Formetric 4D Diers and the angle produced by the scoliometer using the Pearson’s r statistic. Ethics approval: Ethical Approval was granted by the University of West Attica Ethics Committee on the 22/2/2018. 

Results: The internal consistency was shown to be good with Cronbach’s α= 0,71. Test-retest reliability was excellent with ICC= 0,831-0,972, except from the “kyphosis” domain that was moderate with ICC= 0,572. Correlation analysis between GR-SAQ and the “Appearance” domain of GR-SRS-22 demonstrated a significant inverse moderate correlation (r =-0,405, p<0.02, n=33). The “Trunk” shift domain of GR-SAQ correlated highly with the Cobb Angle (r= 0,603, p<0.001, n=33) confirming convergent validity. No statistical significance (p>0.1 at all cases) was noted among the GR-SAQ “Kyphosis” domain and the Cobb angle, the Formetric 4D Diers angle, and the scoliometer angle confirming the different constructs (divergent validity).

Conclusion(s): The Greek version of the SAQ has shown to be a valid, reliable and a tool with similar psychometric properties to the original and to the rest of published cross-cultural adaptations, capable to assess the perception of the spinal deformity of Greek patients with AIS.

Implications: The adapted Greek-SAQ questionnaire with its proven validity and reliability provides therapists in Greece with a popular international tool to compare their data worldwide and to evaluate the perception of spinal deformity and quality of life of their idiopathic scoliosis patients.

Funding, acknowledgements: No Funding was received for this study.

Keywords: Spinal Appearance Questionnaire (SAQ), Cross-cultural validity, Adolescent Idiopathic Scoliosis

Topic: Musculoskeletal: spine

Did this work require ethics approval? Yes

Institution: University of West Attica

Committee: UNIWA Research Committee

Ethics number: 13/22-02-2018