Cross-cultural adaptation and measurement properties of the Back pain Knowledge and beliefs Survey (BacKS) for Chinese adults with or without Low Back Pain.

OBJECTIVES: To adapt the Back pain Knowledge and beliefs Survey (BacKS) into simplified Chinese (BacKS-CN) and evaluate its measurement properties among Chinese adults with or without low back pain (LBP). METHODS: A forward and backward translation was performed. A total of 278 eligible participants (156 LBP participants and 122 healthy individuals) completed an online survey comprising demographic and clinical characteristics, the BacKS-CN and the Back Beliefs Questionnaire (BBQ). Content validity, structural validity, convergent validity, internal consistency, test-retest reliability, measurement error, and floor and ceiling effects were evaluated. RESULTS: The BacKS-CN demonstrated excellent content validity (I-CVI = 0.860-1.000, S-CVI/Ave = 0.993). Exploratory factor analysis supported a three-factor structure. The BacKS-CN total score demonstrated weak correlations with the BBQ across groups (r = 0.29-0.38), indicating limited convergent validity at the total score level. Factor-level correlations with the BBQ were weak for Positive Recovery Beliefs (r = 0.25-0.27), moderate for Fear of Poor Prognosis (r = 0.43-0.46), and negligible to weak for Active Behavioral Coping (r = 0.03-0.14). Internal consistency was modest for the total sample (Cronbach's α = 0.60) and both subgroups (LBP: α = 0.61; healthy: α = 0.58), whereas McDonald's Omega reached acceptable levels across groups (0.69, 0.70, and 0.70, respectively). Test-retest reliability was excellent for the total sample (ICC = 0.89) and both subgroups (LBP: ICC = 0.87; healthy: ICC = 0.91). MDC95% was 5.92 for the total scale. No floor or ceiling effects were observed. CONCLUSION: The BacKS-CN demonstrated acceptable cross-cultural adaptation, good test-retest reliability, and preliminary evidence supporting its validity in assessing knowledge and beliefs about LBP in Chinese adults.