1. The Healthy Heart Study: Using online and mobile risk
calculators to improve cardiovascular disease prevention
Carissa Bonner, PhD Candidate
Supervisors: Kirsten McCaffery, Jesse Jansen, Les Irwig, Ben Newell
Collaborators: Shannon McKinn, Jenny Doust, Paul Glasziou, Armando
Teixeira-Pinto, Haryana Dhillon
Funding: National Health & Medical Research Council, Heart Foundation
The Healthy Heart Study
Screening and Test Evaluation Program (STEP)
Sydney School of Public Health

2. The problem
› CVD prevention guidelines advocate the use of absolute risk 1
› Clinicians report difficulties communicating absolute risk 2
› Probabilistic information is poorly understood by patients and
clinicians 3
› Early research suggests that heart age may be more effective 4
1. Ferket BS, et al. Systematic review of guidelines on cardiovascular risk assessment which recommendations should
clinicians follow for a cardiovascular health check? Arch Intern Med 2010;170:27
2. Bonner C, et al. General Practitioners' use of different assessment strategies in cardiovascular disease prevention: a
qualitative study. Med J Aust 2013; 99:485
3. Visschers V, et al. Probability information in risk communication: A review of the research literature. Risk Analysis
2009;29:267
4. Soureti A, et al. Evaluation of a cardiovascular disease risk assessment tool for the promotion of healthier lifestyles.
Eur J Cardiovascular Prev Rehab 2010;17:519
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3. The approach
› Study 1: Qualitative think aloud study of online calculators
› Study 2: Experiment to test components of online calculator
› Study 3: Experiment to test components of app calculator
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4. Study 1: Results of think aloud study
www.heartagecalculator.com
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5. Study 1: Results of think aloud study
www.knowyournumbers.co.nz
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6. Study 1: Results of think aloud study
EXPECTATIONS
Specific knowledge
General knowledge
EXPERIENCE
Unexpected info =
negative reaction
Expected info =
positive reaction
EVALUATION
Low credibility
High credibility
ACTION
Reject results
See GP for assessment
Consider lifestyle change
Apply to others
Increased knowledge
Changed risk perception

7. Study 2: Development of online experiment
Example: 50 year old male smoker with
raised blood pressure and cholesterol
Your risk of a cardiovascular event in the
next 5 years is 11%. If you stopped
smoking and had lower levels of
cholesterol and blood pressure, your risk
would be 3%.
Your heart age is 74, 24 years older than
you. If you stopped smoking and had
lower levels of cholesterol and blood
pressure, your heart age would be 50, the
same as your current age.
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8. Study 3: Development of app experiment
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9. Collaboration
› What can we offer? Our team has expertise in:
- Psychology: risk communication, decision making, behaviour change,
health literacy and numeracy
- Public health: screening, clinical practice guidelines, older adults
- Mixed methods: qualitative, experimental, intervention RCT, epidemiology
› What do we need? We would like to talk to experts in:
- The use of mobile apps for recruitment and as interventions
- The development of interactive graphics
- Online health information seeking
carissa.bonner@sydney.edu.au
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