Table 4

Adjusted Patient Expenditures by Years of Practice

	Years of Practice				Years of Practice

	All Years		0–7 Years		8–15 Years		16–19 Years

	β (95% CI)	P Value	β (95% CI)	P Value	β (95% CI)	P Value	β (95% CI)	P Value
Sponsoring institution characteristics
Percent of graduates in rural practice	−0.31 (−0.50 to −0.13)	.001	−0.06 (−0.51 to 0.39)	.79	−0.48 (−0.73 to −0.23)	<.001	−0.14 (−0.43 to 0.15)	.36
Percent of graduates in primary care	−0.19 (−0.32 to −0.06)	.004	−0.25 (−0.61 to 0.11)	.17	−0.13 (−0.30 to 0.04)	.12	−0.28 (−0.51 to −0.05)	.02
Sponsoring institution size, natural log	−0.03 (−0.05 to −0.00)	.03	−0.02 (−0.09 to 0.05)	.53	−0.03 (−0.06 to 0.01)	.10	−0.03 (−0.08 to 0.02)	.20
Training HSA spending level^a
Low (−1.49 < z < −0.13)	Reference		Reference		Reference		Reference
Average (−0.14 < z < 0.46)	0.02 (−0.02 to 0.06)	.38	0.14 (0.03–0.25)	.01	−0.00 (−0.05 to 0.04)	.86	0.01 (−0.07 to 0.09)	.75
High (0.48 < z < 4.50)	0.10 (0.05–0.14)	<.001	0.23 (0.10–0.37)	<.001	0.09 (0.03–0.14)	.001	0.04 (−0.05 to 0.13)	.37
Practice HSA spending level
Low ($6,102 to $8,683)	Reference		Reference		Reference		Reference
Average ($8,691 to $9,879)	0.05 (0.01–0.09)	.02	−0.01 (−0.12 to 0.11)	.88	0.06 (0.01–0.11)	.02	0.05 (−0.03 to 0.13)	.20
High ($9,880 to $16,542)	0.08 (0.04–0.12)	<.001	−0.03 (−0.13 to 0.08)	.63	0.11 (0.06–0.16)	<.001	0.06 (−0.02 to 0.15)	.16
Covariates^b	Yes		Yes		Yes		Yes
Patients, No.	502,920		68,691		305,765		128,464
Physicians, No.	3,075		572		1,794		709

HSA = hospital service area.
Note: Data are based on 2011 Medicare Claims. Data are weighted and restricted to primary care physicians with 1–19 years of practice and 40 or more Medicare patients, excluding patients with total expenditures greater than $100,000.
↵a To standardize training HSA spending, we calculated a standardized z score for HSA spending for each year between 1992 and 2010. The training HSA spending groups are Low: −1.49 to −0.14; Average: −0.13 to 0.46; High: 0.48 – 4.50. Each group has approximately the same number of beneficiaries.
↵b Analyses controlled for the patients’ age, sex, race/ethnicity, number of primary care visits, and comorbidity using the weighted Charlson index.