ABSTRACT
OBJECTIVE: The aim of this study was to adapt and validate the Tunisian version of the Oswestry Disability Index (ODI) within a Saudi Arabian population. METHOD: The translation of items 8 and 10 taken out of the Tunisian version was conducted according to Beaton's method. Adaptations were made after a pilot study on 100 patients. The validation study included 100 patients suffering from chronic low back pain aged 18 to 65 years old. Intra-observer reliability was assessed using the intra-class coefficient (ICC). Spearman rank correlation coefficient, the Kruskall-Wallis test and factor analysis were used to evaluate construct validity (convergent and divergent validity). Internal consistency was assessed by Cronbach's alpha coefficient. RESULTS: One hundred Saudi patients were included in the study. Intra-observer reliability was excellent (ICC: 0.99). The correlations of the index with the VAS pain scale (r=0.708), the Roland-Morris Low Back Pain Disability (r=0.656), and the Quebec Back Pain Disability Scale (r=0.792) suggest good construct validity. Factor analysis unveiled two main factors explaining a cumulative percentage variance of 63.5%. The first factor represents static activities and the second factor represents dynamic activities. CONCLUSION: The Arabic version of the ODI adapted to the Saudi population has high metrological qualities. Further studies assessing its responsiveness to change should be conducted.
