Table 2.

Univariate and multivariate analysis of factors associated with use of guideline-based antibiotics.

	N	(%)¹	Univariate OR	Multivariate OR
	19,897	(78.9)
Age
<60 years	9111	(81.3)	Referent	Referent
≥60 years	10,786	(77.0)	0.77 (0.72–0.82)^*	0.89 (0.81–0.98)^*
Gender
Male	8057	(80.8)	Referent	Referent
Female	11,840	(77.6)	0.82 (0.77–0.88)^*	0.82 (0.75–0.90)^*
Year of diagnosis
2000–2003	5563	(75.1)	Referent	Referent
2004–2006	5807	(78.9)	1.24 (1.15–1.34)^*	1.17 (1.06–1.28)^*
2007–2010	8527	(81.5)	1.46 (1.36–1.57)^*	1.40 (1.27–1.53)^*
Race
White	14,541	(79.4)	Referent	Referent
Black	1934	(81.3)	1.13 (1.01–1.26)^*	1.12 (0.98–1.27)
Other	3422	(75.5)	0.80 (0.74–0.87)^*	0.96 (0.87–1.07)
Marital status
Married	11,293	(79.4)	Referent	Referent
Single	2974	(81.5)	1.14 (1.04–1.25)^*	0.98 (0.87–1.09)
Unknown	5630	(76.5)	0.84 (0.79–0.90)^*	0.91 (0.84–0.99)^*
Insurance status
Medicare	8251	(76.4)	Referent	Referent
Medicaid	1746	(81.9)	1.39 (1.24–1.57)^*	1.25 (1.07–1.46)^*
Commercial	8928	(80.5)	1.27 (1.19–1.36)^*	1.19 (1.08–1.30)^*
Uninsured	484	(83.0)	1.51 (1.21–1.88)^*	1.39 (1.07–1.80)^*
Unknown	488	(78.0)	1.09 (0.90–1.32)	1.03 (0.82–1.30)
Location
Metropolitan	17,312	(79.0)	Referent	Referent
Non-metropolitan	2585	(78.2)	0.95 (0.87–1.04)	1.05 (0.91–1.21)
Teaching status
Non-teaching	10,697	(76.0)	Referent	Referent
Teaching	9200	(82.5)	1.49 (1.40–1.59)^*	1.32 (1.18–1.48)^*
Hospital size
<400 beds	8804	(76.7)	Referent	Referent
400–600 beds	5799	(78.7)	1.12 (1.04–1.20)^*	0.94 (0.84–1.07)
>600 beds	5294	(82.9)	1.47 (1.36–1.59)^*	0.97 (0.82–1.13)
Hospital location
Eastern	2706	(82.9)	Referent	Referent
Midwest	4076	(81.0)	0.88 (0.79–0.99)^*	0.90 (0.76–1.06)
Southern	10,535	(78.2)	0.74 (0.67–0.81)^*	0.74 (0.64–0.86)^*
West	2580	(74.6)	0.60 (0.54–0.68)^*	0.77 (0.64–0.92)^*
Comorbidity
<2	2662	(79.6)	Referent	Referent
2	3267	(79.2)	0.98 (0.87–1.09)	0.94 (0.82–1.07)
>2	13,968	(78.6)	0.94 (0.86–1.03)	0.89 (0.79–0.99)^*
Physician specialty
Medical oncology	12,741	(79.5)	Referent	Referent
Internal medicine	3916	(79.1)	0.98 (0.91–1.06)	1.12 (0.99–1.26)
Family practice	1084	(76.0)	0.82 (0.72–0.93)^*	0.98 (0.83–1.17)
Hospitalist	715	(82.8)	1.24 (1.04–1.49)^*	1.49 (1.18–1.88)^*
Other	863	(72.1)	0.67 (0.59–0.76)^*	0.76 (0.63–0.93)^*
Unknown	578	(76.4)	0.84 (0.70–0.99)^*	1.02 (0.74–1.40)
Physician volume
Low	6417	(77.2)	Referent	Referent
Intermediate	6664	(78.6)	1.09 (1.01–1.17)^*	1.10 (0.98–1.23)
High	6816	(80.8)	1.24 (1.15–1.34)^*	1.19 (1.03–1.38)^*
Hospital volume
Low	6256	(74.8)	Referent	Referent
Intermediate	6527	(78.4)	1.23 (1.14–1.32)^*	1.22 (1.08–1.37)^*
High	7114	(83.3)	1.68 (1.55–1.81)^*	1.56 (1.34–1.81)^*
Primary tumor site
Colorectal	1647	(76.9)	0.88 (0.80–0.98)^*	0.87 (0.65–1.16)
Other gastrointestinal	1513	(78.8)	1.00 (0.89–1.12)	0.87 (0.65–1.17)
Head and neck	922	(82.2)	1.25 (1.07–1.46)^*	1.06 (0.78–1.44)
Lung	4800	(77.0)	0.86 (0.81–0.93)^*	0.83 (0.63–1.10)
Breast	5257	(78.5)	0.97 (0.91–1.04)	0.99 (0.75–1.30)
Skin	180	(84.5)	1.47 (1.01–2.13)^*	1.46 (0.91–2.34)
Soft tissue	894	(88.3)	2.08 (1.71–2.53)^*	1.74 (1.24–2.44)^*
Genitourinary	1104	(77.3)	0.91 (0.80–1.03)	0.77 (0.58–1.03)
Gynecologic	1056	(72.4)	0.69 (0.61–0.77)	0.75 (0.55–1.01)
Lymphoma	2582	(84.1)	1.48 (1.34–1.64)^*	1.25 (0.94–1.66)
Brain	169	(74.1)	0.77 (0.57–1.03)	0.60 (0.39–0.93)^*
Infections
Sepsis	2572	(83.3)	1.39 (1.25–1.53)^*	1.32 (1.17–1.48)^*
Pneumonia	1698	(83.2)	1.36 (1.21–1.54)^*	1.40 (1.22–1.61)^*
Intensive care use	227	(14.0)	1.70 (1.48–1.97)^*	1.62 (1.36–1.93)^*
Hypotension	78	(83.0)	1.31 (0.76–2.24)	1.28 (0.70–2.33)
Mechanical ventilation	336	(86.4)	1.71 (1.28–2.29)^*	1.17 (0.83–1.65)

Reflects the percentage of patients who received guideline-concordant care.

p<0.05