Objective The objective of this study was to compare the incidence of work-related injury and illness presenting to Ontario emergency departments to the incidence of worker's compensation claims reported to the Ontario Workplace Safety & Insurance Board over the period 2004–2008.

Methods Records of work-related injury were obtained from two administrative data sources in Ontario for the period 2004–2008: workers' compensation lost-time claims (N=435 336) and records of non-scheduled emergency department visits where the main problem was attributed to a work-related exposure (N=707 963). Denominator information required to compute the risk of work injury per 2 000 000 work hours, stratified by age and gender was estimated from labour force surveys conducted by Statistics Canada.

Results The frequency of emergency department visits for all work-related conditions was approximately 60% greater than the incidence of accepted lost-time compensation claims. When restricted to injuries resulting in fracture or concussion, gender-specific age differences in injury incidence were similar in the two data sources. Between 2004 and 2008, there was a 14.5% reduction in emergency department visits attributed to work-related causes and a 17.8% reduction in lost-time compensation claims. There was evidence that younger workers were more likely than older workers to seek treatment in an emergency department for work-related injury.

Conclusions In this setting, emergency department records available for the complete population of Ontario residents are a valid source of surveillance information on the incidence of work-related disorders. Occupational health and safety authorities should give priority to incorporating emergency department records in the routine surveillance of the health of workers.