Who is Paying the Bills? Health Care Costs for Musculoskeletal Back Disorders, Washington State Union Carpenters, 1989-2003

Objective: Factors associated with private health insurance payment rates for musculoskeletal back disorders were examined among a 15-year cohort of union carpenters. Payment patterns were contrasted with work-related back injury rates over time. Methods: Negative binomial regression was used to assess payment rates; generalized estimated equations accounted for multiple observations per person and cost correlation within subjects. Results: Payment rates increased after work-related injury and with the number of injuries. Increasing private payments and deductibles (inflation-adjusted and discounted) were observed in contrast with a marked decline in reported work-related injuries. Conclusions: Private insurance payments do not appear to be independent of work-related back injury. Findings suggest cost-shifting from workers' compensation to the union-provided health insurance and to the worker; they also provide a warning regarding reliance on workers' compensation statistics for surveillance of work-related disorders or disease.