Simplified Chinese Version of the Back Pain Function Scale (BPFS) for Patients with Low Back Pain: Cross-Cultural Adaptation and Validation

Study design: A cross-sectional study.

Objective: To translate and cross-culturally adapt back pain function scale (BPFS) into a simplified Chinese version (SC-BPFS), and evaluate the reliability and validity of SC-BPFS in patients with low back pain.

Summary of background data: The BPFS is a reliable and valid evaluation instrument for low back pain. However, simplified Chinese version of BPFS has not been validated.

Methods: Cross-cultural adaptation was performed according to the internationally recognized guidelines of the American Academy of Orthopaedic Surgeons Outcome Committee. One-hundred and sixty-two participants with low back pain (LBP) were included in this study. Reliability was tested based on test-retest reliability and internal consistency. We calculated Cronbach alpha and intra-class correlation coefficient (ICC). Construct validity was analyzed by evaluating the correlations between SC-BPFS and the Oswestry disability index (ODI), the visual analogue scale (VAS), and the short form (36) health survey (SF-36).

Results: The original version of the BPFS was cross-culturally well adapted and translated into simplified Chinese. Each item of the SC-BPFS was properly responded and correlated with the total items. SC-BPFS had good reliability (Cronbach alpha = 0.847, intra-class correlation coefficient [ICC] = 0.891, 95% confidence interval [CI] 0.864-0.914). Elimination of any one item in all did not result in a value of Cronbach alpha of <0.80. SC-BPFS had a high correlation with ODI (0.712, P < 0.01) and a moderate correlation with VAS (0.484, P < 0.01). And it was also fairly to very well correlated with physical domains of SF-36 (0.334-0.632, P < 0.01), and not correlated with mental domains of SF-36 (0.022-0.119, P > 0.05).

Conclusion: SC-BPFS demonstrated outstanding acceptability, internal consistency, reliability, and construct validity, and could be recommended for patients with LBP in Mainland China.Level of Evidence: 3.