Translation, cross-cultural adaptation and psychometric properties of the Urdu version of the back pain functional scale in low back pain patients.

Abstract

Translation and validation of important scales in other languages reduce bias in reporting the functional status of the patient. To translate the Back Pain Functional Scale into Urdu (BPFSu), adapt it for use in other cultures, and evaluate its psychometric properties. According to Beaton guidelines, translation and cultural adaption was carried out. On 100 Urdu-literate men and women aged 18-60years with lower back pain, the final BPFSu was assessed for psychometric qualities. First at baseline and again after 7days, participants completed the BPFSu, the Functional Rating Index (FRI), and the Numeric Pain Rating Scale (NPRS). Internal consistency of the BPFSu was excellent (Cronbach's alpha: 0.937). No floor and ceiling effects were found Excellent test-retest reliability (ICC = 0.882, CI 95%; 0.830-0.919) was achieved. Spearman correlation coefficient showed criterion validity with the NPRS (rho =â⁢⁢0.701, p⩽ 0.001) and Pearson correlation coefficient showed construct validity with the FRI (r=â⁢⁢0.740, p⩽ 0.001). The minimum detectable changes were 9.96, while the standard error of measurement was 3.6. The BPFSu is a valid and reliable instrument for assessing physical function in individuals experiencing low back discomfort.