Table 5.

Accuracy of Reclassification of 5‐Year Risk for Major CHD by CAC: Predicted Versus Observed Outcomes

5‐Year Risk Model Without CAC	5‐Year Risk Model With CAC
	0% to <2.5%	2.5% to <5%	5% to <10%	≥10%	Overall	Reclassified as Higher Risk	Reclassified as Lower Risk
0% to <2.5%
No. of participants	2817	138	22	0	2977	160	—
No. of events	22	11	0	0	33	11	—
5‐Year estimate (95% CI)	0.5% (0.3–0.8%)	4.5% (2.1–9.8%)	0%	—	0.7% (0.4–1.1%)	3.9% (1.8–8.4%)	—
2.5% to <5%
No. of participants	119	89	46	7	261	53	119
No. of events	0	1	6	1	8	7	0
5‐Year estimate (95% CI)	0%	1.2% (0.2–8.0%)	7.0% (2.3–20.3%)	14.3% (2.1–66.6%)	2.0% (0.8–4.7%)	8.0% (3.1–20.1%)	0%
5% to <10%
No. of participants	13	26	32	15	86	15	39
No. of events	2	1	6	3	12	3	3
5‐Year estimate (95% CI)	7.7% (1.1–43.4%)	4.0% (0.6–25.2%)	10.7% (3.5–30.2%)	21.4% (7.5–52.8%)	10.1% (5.1–19.2%)	21.4% (7.5–52.8%)	5.2% (1.3–19.2%)
≥10%
No. of participants	1	2	2	11	16	—	5
No. of events	0	0	0	1	1	—	0
5‐Year estimate (95% CI)	0%	0%	0%	14.3% (2.1–66.6%)	9.1% (1.3–49.2%)	—	0%
Overall
No. of participants	2950	255	102	33	3340	228	163
No. of events	24	13	12	5	54	21	3
5‐Year estimate (95% CI)	0.5% (0.3–0.9%)	3.3% (1.7–6.5%)	6.3% (2.9–13.6%)	18.0% (7.9–38.1%)	1.0% (0.7–1.4%)	5.9% (3.5–10.0%)	1.3% (0.3–4.9%)

CAC indicates coronary artery calcification; CHD, coronary heart disease.