Table 3. Cox proportional hazards analysis of the association between MRSA infections and length of hospital stay (compared with MSSA).

Variable	Univariate Model		Multivariate Model
	HR (95% CI)	P	HR (95% CI)	P
MRSA	1.8 (1.2–2.5)	0.002	1.5 (1.0–2.2)	0.046
Prior hospitalizations≥3	1.5 (1.1–2.1)	0.025	1.3 (0.9–1.9)	0.156
COPD	1.2 (0.7–2.1)	0.468	0.9 (0.5–1.7)	0.840
Respirator	2.2 (1.2–3.9)	0.010	1.7 (0.9–3.2)	0.090

HR: Hazard Ratio; COPD: Chronic Obstructive Pulmonary Disease.