Ontario Health Study

The OHS was designed specifically for investigator-initiated retrospective or prospective research.

Unlike general disease or clinical cohorts, the OHS recruited participants regardless of illness or health, so researchers can follow the changes in participant health and exposures over time. Researchers use OHS data and biosamples to assess the effect of genetics, behaviour, family health history and environment on chronic diseases.

The OHS charges access fees on a cost recovery basis. Fees to access data and biosamples are set annually.

To request a cost estimate for your project, submit a Project Feasibility Assessment Form.

Researchers from industry or with private sector interests may apply for access to data and biosamples, and must meet the same rigorous application criteria and derived data requirements as academic applicants.

For more information on who can access the OHS platform and other requirements, please review the OHS Data and Biosample Access Policy.

OHS links personal, behavioural, environmental, health system and biological data so researchers can investigate cancer and chronic disease causes and determinants.

Of the 225,620 OHS participants (recruited 2009-2017), approximately 200,000 (89%) consented to linkage and 83% have been linked to the Ontario Health – Ontario Cancer Registry. The OHS is also linked to ICES data holdings, and to the Ontario Laboratory Information Systems (OLIS), which captures provincial biologic-based laboratory tests.

OHS participants have been linked to CANUE (the Canadian Urban Environmental Health Research Consortium). Linkages with CANUE and Statistics Canada’s Social Data Linkage Environment program allowed for the capture of historical residential exposures levels for ozone, air pollutants, nighttime light and green spaces, as well as climate and weather, making the OHS an ideal platform to study the effect of climate change on the health of participants.

One of our recruitment strategies included offering incentive-based gift cards or Air Miles. Participants recruited with this strategy have been less likely to contribute to follow-up studies or provision of biologic samples.

If this means that the OHS alone is not adequately powered for certain biospecimen-based research projects, the OHS is also part of the pan-Canadian population cohort, CanPath, that has over 150,000 baseline biospecimens available to approved researchers.

Yes, we help other studies recruit OHS participants to be part of their research projects. We have partnered with several investigators that sought to boost recruitment to their studies, or find matching control groups of participants with appropriate disease or demographic profiles.

Visit our Access and Linkage of OHS Data and Biosamples page to learn more about these ancillary studies. Contact access@ontariohealthstudy.ca to discuss your idea with our Research Operations and Access Officer.