Table 2.

Multivariate predictors of the number of tests per patient, squared root cost of tests per patient, empiric days of therapy, and log-transformed length of stay

	Number of tests per patient (negative binomial)			Squared root- cost of tests per patient (linear)			Empiric DOT (zero-inflated model)			Log Length of Stay (linear)
Predictors	Incidence Rate Ratios	CI	P	Estimates	CI	P	Incidence Rate Ratios	CI	P	Estimates	CI	P
(Intercept)	3.96	2.54 – 6.17	<0.001	16.11	7.25 – 24.97	<0.001	6.26	1.16 – 33.80	0.033	1.31	0.45 – 2.18	0.003
Study Period [Post Intervention]	0.83	0.69 – 1.01	0.063	3.46	–0.25 – 7.17	0.068	0.55	0.26 – 1.13	0.102	0.14	–0.23 – 0.50	0.461
Age (Years)	1.00	0.99 – 1.00	0.714	0.05	–0.06 – 0.16	0.359	0.99	0.97 – 1.01	0.467	0.00	–0.01 – 0.01	0.762
Gender [Male]	1.16	0.96 – 1.40	0.118	1.30	–2.36 – 4.97	0.485	0.67	0.33 – 1.36	0.263	0.38	0.03 – 0.74	0.035
Race [Others vs. White]	1.00	0.82 – 1.22	0.997	0.28	–3.52 – 4.08	0.885	0.80	0.38 – 1.67	0.556	0.04	–0.33 – 0.41	0.832
Location [Floor vs. ED]	1.01	0.70 – 1.47	0.943	7.37	–0.04 – 14.77	0.051	3.50	0.90 – 13.70	0.072	–0.18	–0.90 – 0.54	0.625
Location [ICU vs. ED]	0.89	0.60 – 1.32	0.552	7.01	–0.86 – 14.88	0.081	0.82	0.20 – 3.28	0.777	0.93	0.16 – 1.70	0.018
Diabetes	1.96	1.08 – 3.61	0.028	5.23	–8.25 – 18.70	0.445	0.42	0.04 – 3.99	0.449	–0.11	–1.42 – 1.20	0.869
Transplant	1.93	1.39 – 2.70	<0.001	9.86	2.63 – 17.09	0.008	0.79	0.21 – 2.90	0.720	0.79	0.08 – 1.49	0.028
ESRD	1.34	0.83 – 2.17	0.240	6.01	–4.26 – 16.28	0.250	0.73	0.11 – 4.73	0.745	0.35	–0.65 – 1.35	0.495
VP Shunt	0.62	0.38 – 0.99	0.048	–16.36	–24.67 – –8.05	<0.001	0.64	0.14 – 2.95	0.568	0.12	–0.69 – 0.93	0.773
Encephalitis	1.75	0.86 – 3.61	0.119	6.94	–8.52 – 22.40	0.377	0.10	0.01 – 1.48	0.094	–1.44	–2.95 – 0.07	0.061
HIV	1.62	1.17 – 2.24	0.004	12.05	4.96 – 19.14	0.001	0.26	0.08 – 0.86	0.027	–0.11	–0.80 – 0.58	0.757
Observations	231			231			231			231
R2 Nagelkerke	0.275			0.185/0.140			0.619/0.596			0.211/0.168