Validation of the Sinhalese version of the Oswestry Disability Index for low back pain

Introduction: Low back pain (LBP) is a major cause of disability. Oswestry Disability Index (ODI) is used to evaluate the impact of LBP) on daily activities. The objective of the current study was to validate and culturally adapt the ODI to the Sinhalese speaking Sri Lankan population.

Methods: The study was conducted at National Hospital, Sri Lanka, including an 18-65 years aged cohort of 100 patients with chronic LBP. The Sinhalese ODI version 2.1a was validated by assessing the test-retest reliability (Intraclass correlation coefficient), internal consistency (Cronbach α) and constructs validity comparing the ODI with the Roland Morris Disability Questionnaire (RDQ) and Visual Analog Scale for pain intensity (Pearson correlation coefficient).

Results: The mean age (±SD) of the study participants was 50.17±11.20 years and mean duration of LBP among participants were 34.00±43.58 months. The ODI had an overall Cronbach α coefficient of 0.811 (95% CI 0.746- 0.865). An excellent agreement was detected between test and re-test ODI scores, indicated by an ICC of 0.983 (95% CI: 0.975-0.989. The Pearson’s correlation test revealed a significant strong positive correlation between ODI and RDQ (r=0.989, p<0.001) and a moderate positive correlation between ODI and VAS pain intensity (r=0.568, p<0.001).

Conclusion: The Sinhalese translation of the ODI version 2.1a had good reliability, temporal stability, and validity when assessed compared to other standard measures. The ODI can be employed in future studies assessing LBP disability in Sri Lanka.