TABLE 2.

Maximum likelihood estimates of VRE colonization

Variable	Regression coefficient	SE	Probabilitya	Adjusted odds ratio	95% CIb
Intercept	−3.065	0.924	0.001
Age	−0.202	0.078	0.009	0.82	0.70–0.95
Vancomycin	3.920	1.322	0.003	50.39	3.77–672.71
Cefotaxime	3.644	1.405	0.009	38.24	2.43–600.83
Ceftazidime	4.560	1.305	0.001	95.62	7.41–999.00
Chemotherapy	2.327	0.839	0.005	10.25	1.98–53.03
Cefotaxime and vancomycin	−3.957	1.969	0.044
Ceftazidime and vancomycin	−5.202	1.789	0.004

^aWald’s chi-square test. 

^bConfidence interval for odds ratio determined by the formula A_z(SE) = 0.949 (0.029), where A_z is the area under the receiver operating characteristic curve.