Formulas and sources
Duke treadmill score
DTS = exercise time (min) − 5 × max ST deviation (mm) − 4 × angina index
Angina index: 0 none, 1 non-limiting, 2 exercise-limiting. Risk groups: low ≥ +5, moderate −10 to +4, high ≤ −11. Derived in 2,842 inpatients and validated in 613 outpatients with suspected CAD.
Mark DB, Hlatky MA, Harrell FE Jr, Lee KL, Califf RM, Pryor DB. Exercise treadmill score for predicting prognosis in coronary artery disease. Ann Intern Med 1987;106:793–800. DOI
Mark DB, Shaw L, Harrell FE Jr, et al. Prognostic value of a treadmill exercise score in outpatients with suspected coronary artery disease. N Engl J Med 1991;325:849–853. DOI
Achieved METs from Bruce time
Men: VO₂ = 14.8 − 1.379 T + 0.451 T² − 0.012 T³ · Women: VO₂ = 4.38 T − 3.9 · METs = VO₂ / 3.5
T is total exercise time in decimal minutes; VO₂ in mL/kg/min. Values below zero are shown as 0.
Foster C, Jackson AS, Pollock ML, et al. Generalized equations for predicting functional capacity from treadmill performance. Am Heart J 1984;107:1229–1234. DOI
Age-predicted METs and functional capacity
Men: predicted METs = 18 − 0.15 × age · Women: 14.7 − 0.13 × age · % predicted = achieved / predicted × 100
Categories used here: < 60 % poor, 60–79 % fair, 80–99 % average, 100–119 % good, ≥ 120 % high. The men's nomogram comes from 1,388 veterans referred for exercise testing; the women's from 5,721 asymptomatic women in the St James Women Take Heart Project.
Morris CK, Myers J, Froelicher VF, Kawaguchi T, Ueshima K, Hideg A. Nomogram based on metabolic equivalents and age for assessing aerobic exercise capacity in men. J Am Coll Cardiol 1993;22:175–182. DOI
Gulati M, Black HR, Shaw LJ, et al. The prognostic value of a nomogram for exercise capacity in women. N Engl J Med 2005;353:468–475. DOI
Build 2026-09-10.1.