Cross-cultural adaptation of Cantonese (Hong Kong) Oswestry Disability Index version 2.1b

Purpose Oswestry Disability Index (ODI) was established by Fairbank in 1989 to assess functional disabilities in low back pain (LBP). It was last updated in 2019 as ODI version 2.1b (ODI AU_2.1b). ODI was first translated into Simplified Chinese Oswestry Disability Index (CODI) in 2008 by Lue. The construct validity, internal consistency, level of agreement and the floor and ceiling effects of CODI were found unclear by Yao in 2016. This study will verify how well the adapted Cantonese–Hong Kong Oswestry Disability Index version 2.1b (HKCODI) aligns with ODI AU_2.1b in the Southern Chinese population. Methods The translation of ODI AU_2.1b was performed according to guidelines from MAPI Research Trust and American Association of Orthopaedic Surgeons. Psychometric properties of HKCODI were tested statistically by Pearson’s correlation, Cronbach’s Alpha and Intraclass Correlation Coefficient (ICC). Results A total of 200 subjects (109 males, 91 females) aged from 15 to 85 (mean age = 58.91) with LBP scored from 3/10 to 10/10 in the Visual Analogue Scale (VAS) were recruited in the Occupational Therapy Department of a tertiary referral center. HKCODI demonstrated strong construct validity in comparing with Hong Kong Roland–Morris Disability Questionnaire (HKRMDQ) ( r = 0.666, p = 0.000), Short Form Health Survey (SF-36) Physical Composite Summary (− 0.700, p = 0.000) and VAS (0.487, p = 0.000). Excellent internal consistency and test–retest reliability were confirmed with Cronbach’s Alpha of 0.997 and ICC of 0.993 at 95% confidence level. Conclusion Cross-cultural adaptation of ODI AU_2.1b has been translated and validated as HKCODI and Item-8 (Sex Life) was suggested to skip for patient older than 60. HKCODI is a fully self-administered and highly reliable tool in assessing the functional disability of patients with LBP in the Southern Chinese population.