In patients at borderline (5.0–7.4%) and intermediate (7.5–19.9%) risk of ASCVD at 10 years, in whom risk-based preventive decisions remain uncertain, the 2019 guidelines strongly endorse CAC testing (class IIA recommendation) as the preferred test for decision-making. The 2019 guidelines recognize the evidence indicating that patients with a CAC score of 0 are at a low risk of ASCVD events in the subsequent 10 years, and can have statin therapy withheld or postponed4,9,10. Conversely, a CAC score ≥100 Agatston units or ≥75th percentile based on age, sex and race reclassifies the risk upward, and helps to identify those in whom the benefit of statins exceeds the potential for harm4,9,10. This strategy of matching treatment to risk categories is designed to be cost-effective, by selecting patients who are more likely to benefit from therapies, while minimizing adverse effects and costs from overtreatment. Those at high risk of CVD have a greater net benefit from preventive therapies than individuals at lower risk. Hence, risk prediction serves as a framework to engage patients in a discussion about the level of risk, required intensity of lifestyle changes and, if indicated, pharmacological therapy. The 2019 guidelines also support tailoring blood pressure goals according to predicted risk.