Info & tools for Scientists

For Researchers

Project BigLife algorithms are published in peer-review science literature. We embrace open science with additional web appendices, visualization tools and other resources to describe how the algorithms. These resources support further development, validation and use the algorithms. The resources are on our [GitHubrepository] (https://github.com/Big-Life-Lab/predictive-algorithms) and the algorithm publications.

Our Calculators

Cardiovascular Disease Population Risk Tool (CVDPoRT)

A predictive algorithm for 5-year risk of incident cardiovascular disease. Developed and validated using the 2001 to 2008 Canadian Community Health Surveys (CCHS). Cardiovascular incidence is a first hospitalization or death for major cardiovascular event. The main predictors are health behaviours (smoking, diet, physical activity and alcohol consumption). The model is currently calibrated for Canada 2013 with provisions to calibrate to other countries.

There were 104 219 respondents aged 20 to 105 years, 3 709 cardiovascular events, and 818 478 person-years follow-up in the combined derivation and validation cohorts.

5-year cumulative incidence - males = 0.026, 95% confidence interval [CI] 0.025–0.028; females = 0.018, 95% 0.017–0.019.

Discrimination - c-statistic: male model = 0.82, 95% CI 0.81–0.83; female model = 0.86, 95% CI 0.85–0.87.

Calibration - overall population 5-year observed cumulative incidence versus predicted risk: males = 0.28%; females = 0.38%. Calibration slope females: 0.9734, SE 0.0698; for males: 0.9295, SE 0.0731. Observed versus predicted < 20% difference in predefined policy-relevant subgroups (206 of 208 groups) at P

Trial registration: ClinicalTrials.gov, no. NCT02267447

Reference data

Additional reference data includes:

• An interactive algorithm visualization tool that displays the contribution of the main predictors and the role of age and exposure interactions.

• CVDPoRT model in XML format (Predictive Modelling Markup Language);

• 500 beta coefficients to calculate statistical uncertainty; and,

• Fictitious examples (n = 20 000) of exposure input and output, including intermediate calculation steps.

See the API/developer page for additional information.

References

Manuel, D., Tuna, M., Bennett, C., Hennessy, D., Rosella, L., Sanmartin, C., . . . Taljaard, M. (2018). Development and validation of a cardiovascular disease risk-prediction model using population health surveys: the Cardiovascular Disease Population Risk Tool (CVDPoRT).
Canadian Medical Association Journal,190(29), E871-882. doi:doi: 10.1503/cmaj.170914

Taljaard, M., Tuna, M., Bennett, C., Perez, R., Rosella, L., Tu, J. V., . . . Manuel, D. G. (2014). Cardiovascular Disease
Population Risk Tool (CVDPoRT): predictive algorithm for assessing CVD risk in the community setting. A study protocol.
BMJ Open, 4(10), e006701.doi:10.1136/bmjopen-2014-006701


Cardiovascular Disease Risk (Heart Attack and Stroke Calculator)

"What sets this cardiovascular risk calculator apart from other calculators worldwide is that it looks at healthy living, and it is better calibrated to the Canadian population," says Dr. Doug Manuel, lead author of the Cardiovascular Disease Population Risk Tool (CVDPoRT) in the Canadian Medical Association Journal.

‍The calculator uses responses from 104,219 Ontario residents from the Canadian Community Health Surveys (2001 to 2007) linked to hospitalizations and deaths to develop and validate CVDPoRT.


"People are interested in healthy living, but we don't often have that discussion in the doctor's office," says Dr. Manuel. "Doctors will check your blood pressure and cholesterol levels, but they don't necessarily ask about lifestyle factors that could put you at risk for a heart attack and stroke. We hope this tool can help people—and their care team—obtain better information about healthy living and options for reducing their risk of heart attack and stroke."

The calculator allows individuals to predict their risk of hospitalization or death from cardiovascular disease within the next five years. For example, if their risk if 5%, it means that 5 in 100 people like them will experience a serious cardiovascular event in the next five years. The calculator also provides heart age, an easy-to-understand measure of heart health.

In addition to personal use, policy-makers can use the tool to calculate risk profiles for different populations. Currently set up for use in Canada, it can be adapted for any of the 100 countries around the world that collect health survey data.

Mortality PopulationRisk Tool (MPoRT)

"Unhealthy behaviours place a major burden on Canadian life expectancies," said lead author Dr. Doug Manuel, senior scientist at The Ottawa Hospital and professor at The University of Ottawa, and a senior core scientist at the Institute for Clinical Evaluative Sciences (ICES). "This study identified which behaviours pose the biggest threat."

The study found:
• 26 % of all deaths are attributable to smoking
• 24 % of all deaths are attributable to physical inactivity
• 12 % of all deaths are attributable to poor diet
• 0.4 % of all deaths are attributable to unhealthy alcohol consumption

The life expectancy calculator was developed using a statistical model to estimate the risk of death associated with smoking, unhealthy alcohol consumption, poor diet, and physical inactivity in Ontario.

"Our approach is a new way of measuring the impact of health problems on life expectancy," said Dr. Manuel. "In an era of big data, we should be moving beyond the old methods that have remained largely unchanged for the past 60 years."

Tools

CCHS Flow

cchsflow supports the use of the Canadian Community Health Survey (CCHS) by transforming variables from each cycle into harmonized, consistent versions that span survey cycles (currently, 2001 to 2014).

https://big-life-lab.github.io/cchsflow/

Algorithm Viewer

http://algorithm-viewer.projectbiglife.ca/#/

Github

Check out PBL's Github repositories - Big Life Lab Flow (BLLFlow) - a workflow for open, reproducible research.
https://github.com/Big-Life-Lab