TABLE 2.

Multivariable Model of Risk Factors for Colonization With Fluoroquinolone (FQ)–Resistant Escherichia coli

Variable	Regression coefficient (SE)	Adjusted OR (95% CI)	P
Intercept	−2.16 (0.31)		<.001
FQ use in prior 30 daysa	−0.03 (0.61)	0.97 (0.29–3.23)	.96
Greater median time from admission to samplingb	0.02 (0.01)	1.02 (1.01–1.03)	.003
Stay at Penn Presbyterian Medical Centerc	0.94 (0.30)	2.56 (1.41–4.64)	.002
Year of enrollmentd
2003	−0.32 (0.34)	0.72 (0.37–1.42)	.35
2004	−1.22 (0.43)	0.30 (0.13–0.69)	.005
Interaction between FQ use and enrollment
In 2003	0.37 (0.75)	1.45 (0.33–6.33)	.62
In 2004	2.31 (0.78)	10.16 (2.21–46.64)	.003

NOTE. CI, confidence interval; OR, odds ratio; SE, standard error.

^aCoefficient and OR reflect those subjects enrolled in 2002.

^bCoefficient and OR associated with each increase of 1 hospital day.

^cAs opposed to the Hospital of the University of Pennsylvania.

^dCoefficient and OR reflect those subjects without prior FQ use.