What is the Duke Treadmill Score formula?

DTS = Exercise Time (minutes) − (5 × Maximum ST Deviation in mm) − (4 × Angina Index). The angina index is 0 for no angina, 1 for non-limiting angina, and 2 for exercise-limiting angina.

What do the risk categories mean?

A score of +5 or higher is low risk (estimated 5-year survival ≥97%, annual mortality <1%). Scores from −10 to +4 are moderate risk (~85% 5-year survival, ~2–3% annual mortality). Scores below −10 are high risk (~65% 5-year survival, ~5% annual mortality).

What exercise protocol does this score apply to?

The Duke Treadmill Score was validated using the standard Bruce treadmill protocol. Results from other protocols may not translate directly.

Is ST elevation or depression used?

Both ST depression and ST elevation are used as the absolute deviation from baseline. Use the maximum value observed regardless of direction.

Can I use this calculator for a patient decision?

This tool is for educational and reference purposes only. All clinical decisions must be made by a qualified healthcare provider who reviews the complete patient history, ECG, and clinical context.

Who developed the Duke Treadmill Score?

The score was developed by researchers at Duke University Medical Center and published by Mark et al. in the New England Journal of Medicine in 1991.

Duke Treadmill Score Calculator

Enter exercise time, ST deviation, and angina index from a treadmill stress test to get the Duke Treadmill Score and cardiovascular risk category.

Stress Test Inputs

Exercise Time (minutes)

Total duration completed on the treadmill (Bruce protocol).

Max ST Deviation (mm)

Maximum ST-segment depression or elevation observed (absolute value).

Angina Index

Chest pain experienced during the test.

0 — No angina No chest pain during the test. 1 — Non-limiting angina Chest pain occurred but did not stop the test. 2 — Exercise-limiting angina Chest pain was the primary reason the test was stopped.

Enter your stress test values and click Calculate to see the Duke Treadmill Score.

Duke Treadmill Score

Formula Breakdown

DTS = Time − (5 × ST Deviation) − (4 × Angina Index)

Prognosis Reference

Risk	Score Range	5-Year Survival	Annual Mortality
Low	≥ +5	≥ 97%	< 1%
Moderate	−10 to +4	~85%	~2–3%
High	< −10	~65%	~5%

Medical Disclaimer: This calculator is for educational and reference purposes only. It does not constitute medical advice. Always consult a qualified healthcare professional for clinical decisions.

Summary

The Duke Treadmill Score (DTS) is a validated clinical tool used to estimate cardiovascular risk following a standard Bruce-protocol exercise stress test. It combines three variables — exercise duration, maximum ST-segment deviation, and angina index — into a single numeric score that predicts 5-year survival and annual mortality risk. Scores of +5 and above indicate low risk, -10 to +4 indicate moderate risk, and below -10 indicate high risk requiring further evaluation.

How it works

Enter the total exercise time in minutes completed during the treadmill stress test.
Input the maximum ST-segment deviation in millimeters (elevation or depression) observed during or after exercise.
Select the angina index: 0 if no angina occurred, 1 if non-limiting angina, or 2 if angina was the reason the test was stopped.
The calculator applies the Duke formula: Score = Exercise Time − (5 × ST Deviation) − (4 × Angina Index).
Your score is displayed along with the corresponding risk category (low, moderate, or high) and estimated 5-year survival rate.

Use cases

Quickly interpret treadmill stress test results in a clinical or educational setting.
Estimate 5-year survival probability and annual cardiovascular mortality risk.
Triage patients into risk categories to guide further diagnostic workup.
Support shared decision-making between clinicians and patients after stress testing.
Cross-check manual score calculations to avoid arithmetic errors.
Educational tool for medical students learning exercise stress test interpretation.

Frequently Asked Questions

Last updated: 2026-09-30 · Reviewed by Nham Vu