Physical workplace factors and return to work after compensated low back injury: A disability phase-specific analysis

Little is known about predictors of duration of work disability (DOD). This cohort study of 433 workers' compensation claimants estimated DOD for job injury, and demographic factors during consecutive disability phases using Cox regression analysis. DOD was calculated from administrative records. Re sults show that DOD in creases with the time spent bending and lifting or p ushing or pulling heavy objects at work, but it is unrelated to sitting; st anding, or vibration. Younger age, longer pre-injury employment, less sever e injuries, and a previous back injury predicted shorter disability, the fa tter factor only during the subacute/chronic disability phases. The effect of injury severity decayed over time. This study demonstrates the usefulnes s of a phase-specific analysis and shows that physical job and injury facto rs have a significant and time-varying impact on DOD.