Risk Calculators

The Society offers two risk calculators that cardiothoracic surgeons can use in their practices.

STS Short-Term Risk Calculator - Updated

Please note: As of November 15, 2018, The Society of Thoracic Surgeons released an updated short-term risk calculator to reflect the latest 2018 adult cardiac surgery risk models. You can read about these updated risk models in The Annals of Thoracic Surgery (Part 1—Background, Design Considerations, and Model Development and Part 2—Statistical Methods and Results.)

The STS Short-Term Risk Calculator allows you to calculate a patient’s risk of mortality and morbidities for the most commonly performed cardiac surgeries. The Risk Calculator incorporates STS risk models that are designed to serve as statistical tools to account for the impact of patient risk factors on operative mortality and morbidity.

Step-by-step instructions have been prepared to show you and members of your cardiothoracic surgery team how to access and use the new risk calculator.


ASCERT Long-Term Survival Probability Calculator

The ASCERT Long-Term Survival Probability Calculator for Isolated CABG allows a user to calculate survival probability following isolated coronary artery bypass grafting surgery in patients 65 years and older. The calculator incorporates a risk model derived from linking STS Adult Cardiac Surgery Database data (version 2.52) to Centers for Medicare & Medicaid Services MEDPAR data as part of the STS-ACC ASCERT grant.


Statistical Methodology for STS Risk Models and Performance Measures

View the STS Surgeon Composite Technical Appendix