Risk of injury by unionization survival analysis of a large industrial cohort

Abstract

Objective: To investigate the effect of union status on injury risk among a large industrial cohort. Methods: The cohort included hourly employees at 19 US plants between 2000 and 2007. Plants were classified by union status, and injuries were classified by severity. Cox-proportional hazard shared frailty model was used to determine time to first reportable injury. Results: A total of 26,462 workers were included: 18,955 (72%) unionized and 7507 (28%) non-unionized. Union workers incurred 3194 injuries (16.9%) compared with 618 injuries for non-union workers (8.2%). After adjusting for multiple covariates, union workers had a 51% higher risk of reportable injury. Conclusions: Our results provide evidence for higher risk of reportable injuries in union workers; explanations for this increased risk remain unclear.