Journal of occupational rehabilitation
-
Comparative Study
Concurrent validity of questionnaire and performance-based disability measurements in patients with chronic nonspecific low back pain.
This study aimed to investigate the concurrent validity of two approaches to disability measurement in patients with chronic nonspecific low back pain (CLBP). It was hypothesized that if both are measuring the same construct, the instruments would lead to similar disability results and would correlate strongly (r > 0.75). The study compared the results of self-reported and performance-based measures of disability in 64 consecutive patients with CLBP. ⋯ In contrast the results from the performance-based measures suggested that the subjects should be able to work at a physical intensity level of moderate to heavy. Little to moderate correlation was observed between the self-report and performance-based measures (Spearman rank correlations: Roland-FCE (-0.20), p > 0.05; Oswestry-FCE (-0.52), p < 0.01; Quebec-FCE (-0.50), p < 0.01). Results are interpreted to suggest that both performance-based and self-report measures of disability should be used in order to obtain a comprehensive picture of the disability in patients with CLBP.