Comparison of Compensated Low Back Pain Claims Experience in Australia with Limb Fracture and Non-Specific Limb Condition Claims: A Retrospective Cohort Study.

Objectives To describe the incidence, duration, and patterns of working time loss claims in compensated Australian workers with low back pain (LBP), and compare this with limb fracture (LF) and non-specific limb condition (NSLC) claims. Methods The National Dataset for Compensation-based Statistics was used for this study. Accepted workers' compensation time loss claims for LBP, LF or NSLC occurring between July 2010 and June 2015 were included. Counts, rates per 10,000 covered workers, the relative risk and median duration of time loss were calculated. Multivariate Cox and quantile regression models were used to determine factors affecting time loss duration and patterns. Results There were 56,102 LBP claims, 42,957 LF claims, and 18,249 NSLC claims. The relative risk of a claim for LBP was significantly greater than LF after adjustment for all covariates (ARR 1.30, 95% CI 1.29-1.32, p < 0.001). LBP claims had similar median time loss (9.39 weeks) to LF claims (9.21 weeks). Claims for LBP were significantly more likely to be resolved in the early phase (10th and 25th quantiles of time loss; 25th quantile: - 1.12 weeks, 95% CI - 1.20 to - 1.05) than claims for LF, but significantly less likely to be resolved in the later phase (75th and 90th quantiles; 75th quantile: 7.02 weeks, 95% CI 6.42-7.61). Claims for NSLC had generally greater time loss than claims for LF, but less time loss than LBP above the 90th quantile. Conclusions The risk of a claim for LBP is higher than LF and NSLC. Although LBP claims are more likely to resolve in the early phase than limb fracture and NSLC claims, LBP claims have longer durations when workers are away from work more than seven weeks.