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Together, we’re leading the fight against cancer and chronic disease.

We asked, you answered. The Ontario Health Study (OHS) research platform is now 15 years old. More than 225,000 volunteers across the province are making their personal health information available to researchers, opening the doors to potential new discoveries and strategies for preventing, detecting and treating cancer and chronic disease.

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See how health scientists are using the data you’ve provided and complete online questionnaires to keep on contributing to the growing OHS platform.

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Access ready-to-use, high-quality epidemiological, clinical and biological datasets that can be easily linked to a wide range of administrative health data.

What’s being studied?

The OHS explores the ways lifestyle, the environment and genetics affect people’s health. With nearly 225,000 volunteers contributing health data over the course of their lifetimes, it’s one of Canada’s largest long-term health studies. It’s also part of something even bigger, feeding into CanPath, the Canadian Partnership for Tomorrow’s Health: the largest health research platform in Canadian history

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Volunteer participants across Ontario

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Non-fasting blood samples

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Urine samples

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Physical measurements

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While we are not seeking new volunteers for the study, participants who have already signed up will continue to provide information on topics such as social and economic demographics, personal and family health histories, sleep patterns, medication and over-the-counter drug use, alcohol and tobacco use, cannabis and e-cigarette use, physical activity, mental health and environmental exposures.

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New email address? Moving?
Let us know!

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Your de-identified data 
is making a difference.

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Curious about who helped choose the data to be collected in this study?

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Online questionnaires give you the chance to tell us how your health has changed over time.