Study design: Translation, cross-cultural adaptation, and validation were performed on the Chinese version of the Oswestry Disability Index (ODI).
Objective: The objective of this study was to translate and adapt the ODI into simplified Chinese and to then validate its use in Chinese patients with low back pain.
Summary of background data: A traditional Chinese version of the ODI (TCODI) has been developed and used in Hong Kong. However, there is no simplified Chinese version of the ODI (SCODI).
Methods: Translation and cross-cultural adaptation of the latest version of the ODI (2.1a) were performed following instructions from the published international guidelines. The translation procedure included forward translation, back translation, and a discussion among experts. The prefinal version was tested in 40 outpatients with LBP. Then, 179 patients with LBP, including 140 outpatients and 39 inpatients, participated in the final test. They finished the SCODI, the Short-Form 36, and the Visual Analog Scale. Those 39 inpatients also finished a second ODI questionnaire within 24 hours. Last, the SCODI and TCODI were tested in another 25 inpatients for comparison.
Results: All of the patients in the prefinal test understood the simplified Chinese version correctly. In the final test, Cronbach's alpha for internal consistency was 0.93. A very high intraclass correlation coefficient was observed (ICC = 0.99) in the test-retest group. The SCODI showed a significant correlation with the 8 subscales of the Short-Form 36, especially in physical functioning (r = 0.78, P < 0.001). There was a moderate correlation between the ODI scores and the Visual Analog Scale (r = 0.69, P < 0.001). A significant difference in the mean score was demonstrated between the SCODI and the TCODI. Patients who participated in the comparison test all agreed that the SCODI was easier to understand than the TCODI.
Conclusion: The results showed that the translation and adaptation were successful. The SCODI has proven to be valid and reliable when used in the simplified Chinese speaking population.