(a).

Variables	β	Standard error	p value	Odds ratio	95% CI odds ratio (lower-upper)
NAT suspected	2.434	0.989	0.014	11.40	1.64–79.25
PRISM III score	0.222	0.072	<0.005	1.25	1.08–1.44
Age	0.039	0.094	0.679	1.04	0.87–1.25
Admission GCS	−0.303	0.226	0.179	0.74	0.47–1.15
Initial Hgb	−0.057	0.042	0.174	0.95	0.87–1.03
RBC transfusion	−5.688	5.366	0.289	0.00	0.00–125.17
Initial Hgb ∗ RBC transfusion	0.046	0.045	0.302	1.05	0.96–1.14
Constant	3.094	5.468	0.572	22.06

R ² = 0.586; χ² = 51.1.