The purpose of this study is to develop, evaluate, and apply a predictive algorithm for assessing CVD risk in the community setting: the Cardiovascular Disease Population Risk Tool (CVDPoRT).

This observational study will use the Ontario sample of the Canadian Community Health Survey (2001, 2003, 2005; 77,251 respondents) to assess risk factors - focusing on health behaviours (physical activity, diet, smoking, and alcohol use). Incident CVD outcomes will be assessed through linkage to administrative healthcare databases (619,886 person-years of follow-up until 31 December 2011). Socio-demographic factors (age, sex, immigrant status, education) and mediating factors such as presence of diabetes and hypertension will be included as predictors. Risk prediction models will be developed using competing risks survival analysis. The analysis plan adheres to published recommendations for the development of valid risk prediction models to limit the risk of over-fitting and improve the quality of predictions. Key considerations are fully pre-specifying the predictor variables; appropriate handling of missing data; use of flexible functions for continuous predictors; and avoiding data-driven variable selection procedures that increase the risk of type I error. The 2007 and 2009 surveys (approximately 50,000 respondents) will be used for validation. Calibration will be assessed overall and in predefined subgroups of importance to clinicians and policymakers.

Inclusion Criteria:

• Respondents to the Canadian Community Health Surveys

Exclusion Criteria:

• Not eligible for Ontario's universal health insurance program
• Pregnant
• Prior history of heart disease or stroke
• Younger than age 20

The derivation cohort will be eligible respondents to the combined 2001, 2003 and 2005 Canadian Community Health Surveys, conducted by Statistics Canada. The validation cohort will consist of respondents to the 2007 and 2009 surveys.

The final model parameters will be provided in Predictive Modelling Markup Language (PMML) and Lime questionnaire files; as well, we will provide a mock dataset. These files can be used to generate risk estimates in computer applications.

Ontario respondents of CCHS survey cycles 1.1, 2.1, 3.1 and 4.1 (conducted in 2001, 2003, 2005 and 2007, respectively). Respondents were excluded if they were not eligible for Ontario's universal health insurance program, were pregnant, self-reported a prior history of heart disease or stroke, or were age <20 at the time of survey administration.

no adverse event assessment/reporting