Enhancing Ontario labour force denominator information

Reasons for the study

Understanding the rate at which something occurs (e.g. per person or unit of time) is a core principle in epidemiology. Rates allow for meaningful comparisons of the risk of an event occurring among different segments of the labour market, including the risk of a work-related injury. For example, rates allow for risk-of-injury comparisons by gender, age, industry and/or size of workplace.

To calculate a rate, you need to know the number of people affected (the numerator) out of the possible number of people possibly affected (the denominator). The more accurate the denominator, the truer the rate. When calculating work-related injury risks, the denominator is the labour force or portion of the labour force of interest.

While both emergency department and workers’ compensation claims are sources of information on injury events in Ontario, only workers’ compensation data includes detailed information on relevant measures such as occupation, industry and workplace size. However, the challenge with workers’ compensation data as a source of injury information in Ontario is that not all labour force participants in the province are insured with the collector of this data—the Workplace Safety and Insurance Board (WSIB). As such, labour force estimates have to be adjusted for differential WSIB coverage before they are combined with workers’ compensation claims to produce rates of claims per worker or per hour worked.

It is also important to examine rates of workers’ compensation claims across different types of occupational exposures to inform prevention targets. Available sources of information on occupational exposures have to be linked to Canadian occupational coding standards to enable them to be used in estimating claim rates.

This project aims to enhance denominator information related to Ontario's labour force in order to provide more robust rates of workplace injury.

Objectives of the study

  • Estimate rates of workers’ compensation claims and emergency department visits in the Ontario labour market 

Target audience

MLITSD; OHS policy-makers and decision-makers in Ontario; employers, workers, labour representatives and OHS professionals

Project status


Research team

Collaborators and partners

Ministory of Labour, Immigration, Training and Skills Development (MLITSD) Prevention Division and Data Analytics and Research Branch; WSIB Advanced Analytics

Funded by

Ontario Ministry of Labour, Immigration, Training and Skills Development