ABSTRACT
OBJECTIVE: To translate into Arabic and validate the Oswestry index for low back pain in an Arab population. BACKGROUND: No functional disability index to assess low back pain written in the Arabic language and validated in an Arab population is available. DESIGN: Arabic translation of the Oswestry index was obtained by the "forward translation/backward translation" method. Adaptations were made after a pilot study involving ten patients aged 18 to 65 years old. Impairment outcome measures (pain as measured on a visual analog scale [VAS], Schober-McRae, index, duration of morning stiffness and number of night awakenings), disability (Quebec index, Waddell index), handicap (as measured on a VAS) and Beck depression scale scores were recorded. Inter-rater reliability was assessed by use of the intra-class correlation coefficient (ICC) and the Bland and Altman method. Construct validity was investigated with use of the Spearman rank correlation coefficient (convergent and divergent validity), and factor analysis was performed. Internal consistency was assessed by use of the Cronbach alpha coefficient. RESULTS: Eighty Tunisian patients with low back pain were included in the validation study. Two items were excluded. Inter-rater reliability was excellent (ICC = 0.98). Expected divergent and convergent validity results suggested good construct validity. Two main factors were extracted by factor analysis and explained 58.19% of the cumulative variance: the first factor represented discomfort in dynamic activities, the second discomfort in static activities. The Cronbach alpha coefficient was 0.76 for factor 1 and 0.70 for factor 2. CONCLUSION: We translated into and adapted the Oswestry index for the Arabic language in a population of Tunisian women? with low back pain. The 8-item version is reliable and valid. Although the scale was validated in a Tunisian population, we expect that it is suitable for other Arab populations, especially North Africans. Further study is needed to confirm such a hypothesis.
