Table 1.

Characteristics of All Community-Based Office Practices vs. Hospital-Based Practices and Physician-Owned vs. Hospital-Owned Community Office Practices^a

	All Community Office Practices (n=9,783) (ref)	Hospital-Based Practices (n=16,306)	P- value	Physician-Owned Community Office Practices (n=10,395)	Hospital-Owned Community Office Practices (n=1,038)	P-Value
1997–2011				1997–2013
Mean Age (Years)	49.1	44.5	<.001	49.7	49.6	.88
Female	62.7	65.0	.011	62.5	62.8	.85
Race/Ethnicity			.001			<.001
White	77.8	72.5		76.5	85.4
Black	10.2	15.1		10.7	8.7
Hispanic	7.6	9.2		8.2	3.2
Other	4.4	3.1		4.6	2.7
Mean Charlson Comorbidity Count	0.048	0.043	.39	0.049	0.041	.27
Acute Symptoms	72.2	77.8	.001	71.2	77.1	.015
Insurance			<.001			.68
Private	59.2	45.2		53.2	54.6
Medicare/Medicaid	26.4	33.3		23.9	24.5
Other	14.4	21.6		22.9	20.9
Provider identifies as PCP	81.9	52.7	<.001	82.7	82.1	.79
Urban Location	81.7	74.9	.051	82.4	79.4	.40
Geographic Region			.013			<.001
Northeast	20.3	17.6		21.3	16.5
Midwest	24.1	34.7		21.4	38.0
South	37.6	32.8		38.3	37.3
West	18.1	14.9		19.0	8.2
Complaintsb
URIs	36.0	38.1	.20	35.3	37.8	.31
Back Pain	47.1	45.0	.14	48.4	45.9	.23
Headache	18.2	18.1	..94	17.7	17.2	.79

PCP = primary care provider, URI = upper respiratory infection

^aHospital-based outpatient practice data are only available from 1997–2011.

^bComplaint group proportions may not add to 100% because a small number of patients fit into more than one category.