- OBJECTIVE: To examine trends in health care usage and expenditures associated with no-lost-time claims in Ontario over a 15-year period. METHODS: A secondary analysis of administrative workers' compensation claims occurring between 1991 and 2006 (N = 2,290,101). We used regression analysis to model health care expenditures using a zero-inflated linear model, adjusting for age, gender, industry group and size of payroll. RESULTS: The probability of using health care increased over the time period. Health care expenditures per claim declined between 1991 and 1997, but then increased between 1998 and 2006, coinciding with the introduction of occupational health and safety legislation promoting early return to work in Ontario. CONCLUSIONS: Our results provide support to the hypothesis that the increasing use of workplace accommodation since 1998 is a driver of the relatively stable rate of no-lost-time claims in Ontario.