Ontario Health Study

• Non-fasting blood samples were collected from more than 41,000 participants.
• The repository holds serum, plasma, red blood cells and buffy coat.
• For a subset of participants, (~6,000) there are lymphocytes in DMSO.
• ~6,400 samples have been genotyped through a Canadian Partnership for Tomorrow’s Health initiative using the UKBIObank Affymetrix arrays. Inflammatory markers have been assayed for a subset, including cytokine panels from 1,440 participants.
• Urine samples and physical measures were collected from 12,600 and 13,400 participants respectively. Physical measures include anthropometrics, blood pressure, resting heart rate, body fat percentage, grip strength and spirometry.

Physical measures and blood samples were collected through a variety of Study initiatives:

Regional assessment centres

Located in Mississauga, Owen Sound and Sudbury, men and women regardless of their health history were enrolled and invited to the nearest centre where they completed self- and interviewer-administered questionnaires, provided a number of physical measures and provided blood and urine samples. The assessment centres opened in 2009 and closed in July 2010. Approximately 7,600 participants were recruited.

Toronto assessment centre

Starting in 2013, a subset of participants visited an assessment centre in downtown Toronto and provided a series physical measures, completes a computerized cognitive battery, and provided blood and urine samples. Participants also had the opportunity to participate in a home sleep study. This centre was closed March 2014.

Local study centres

The OHS hosted a series of temporary blood collection clinics in communities across the province. More than 50 clinics were held from summer 2014 until March 2017.

LifeLabs blood collection program

Through a partnership with LifeLabs Medical Laboratories, participants were able to provide samples at LifeLabs locations across Ontario. This program ran until March 2017.

• The Ontario Sleep Health Study collects accelerometry and sleep respiratory function from approximately 4,000 participants.
• The Canadian Urban Environmental Health Research Consortium (CANUE) is working to provide researchers with an index measuring exposures to air and noise pollution, green space and much more, for every postal code in Canada. By providing this location-based exposure data to studies like the OHS and many others, CANUE will allow environmental exposure data to be linked to our participants, providing additional information and making our platform even more useful to health researchers.
• The Canadian Alliance for Healthy Hearts and Minds has collected MRIs, and conducted Food Frequency Questionnaires and cognitive assessments from more than 3,000 participants.

Changes in participant cancer diagnoses at follow-up

Of the more than 20,000 participant-reported cancer diagnoses, the most common cancers identified at follow-up are below.