Table 3.

Brier Score of the three clinical models and the three administrative models, for all cardiac surgery and for only isolated coronary artery bypass surgery

	All cardiac surgery			Isolated CABG surgery
Brier scores	Administrative	Clinical	p Value difference	Administrative	Clinical	p Value difference
Original models	2.9% (2.8–3.0)	3.0% (2.8–3.2)	0.093	1.3% (1.2–1.5)	1.4% (1.1–1.7)	0.030
Updated models	2.9% (2.7–3.1)	2.7% (2.5–2.9)	<0.001	1.3% (1.1–1.4)	1.2% (1.0–1.3)	<0.001
Updated+interaction terms	2.8% (2.6–3.0)	2.6% (2.5–2.8)	<0.001	1.2% (1.1–1.4)	1.2% (1.0–1.3)	0.026

Brier scores range from 0 to a value depending on the prevalence of the outcome. The maximum Brier score that was possible in this data was 3.0% for all cardiac surgery and 1.3% for isolated CABG. A lower Brier score indicates better calibration. Brackets denote 95% CIs.

CABG: coronary artery bypass grafting.