Table 6.

Comparison of C Statistic for Model 2 (Without Any ECG Parameters) and Changed Area Under the Receiver Operating Characteristic Curve After Addition of 1‐by‐1 ECG Parameters

Parameter	C Statistic (95% CI)	P Value
Model 2 (without any ECG markers)	0.809 (0.782 to 0.836)	Reference
Spatial TT′ angle, °	0.815 (0.788 to 0.842)	0.053
Heart rate, bpm	0.809 (0.782 to 0.836)	0.882
QTc interval, ms	0.809 (0.781 to 0.836)	0.953
QRS axis, °	0.812 (0.785 to 0.839)	0.284
T axis, °	0.809 (0.782 to 0.836)	0.694
Spatial peak QRS‐T angle, °	0.814 (0.788 to 0.841)	0.100
Spatial T‐vector magnitude, mV	0.809 (0.782 to 0.837)	0.669
Model 3 (with all ECG markers)	0.822 (0.796 to 0.849)	0.021

Model 2 adjusted for age, sex, race, study center, cardiovascular disease, use of β‐blockers, use of antihypertensive medications, systolic blood pressure, diabetes, smoking status, total cholesterol, high‐density lipoprotein cholesterol, triglycerides, albumin, body mass index, leisure activity index, alcohol use, sodium level, and magnesium level. Model 3 additionally adjusted for heart rate, corrected QT interval, spatial QRS‐T angle, QRS axis, T‐wave axis, and spatial T‐vector magnitude. TT′ angle indicates angle between consecutive T‐wave vectors.