Exhibit 1.

Characteristics of physicians participating and not participating in PCIP for all eligible physicians and the propensity score matched sample

	PCIP physicians	All Comparison physicians	Matched Comparison physicians
N	360	4,645	360
Location*Ψ (%)
New York City	100	43.7	90.8
Long Island	0	23.3	5.0
Hudson Valley	0	17.8	1.9
Capital Region and Northern New York	0	12.4	0.6
Western New York	0	2.8	1.7
Percent poverty in zip code†*(mean, sd)	20.1 (6.7)	13.6 (8.0)	20.0 (6.9)
Number of physicians in practice* (mean, sd)	2.1 (2.7)	5.4 (16.8)	1.8 (1.9)
Specialty* (%)
Internal medicine	41.4	41.2	41.7
Family practice	15.8	21.4	14.7
Pediatric medicine	19.2	16.4	21.7
Cardiology	2.8	3.1	2.8
Pulmonology	3.6	1.8	2.2
Gastroenterology	3.1	2.0	3.9
Other	14.2	14.2	13.1
Degree* (% with MD)	94.4	91.0	92.5
Practice ownership* (% with corporate parent)	6.7	26.0	4.4
Number of technical assistance visits¥ (mean, sd)	3.1 (3.7)	-	-
Exposure to PCIP¥ (%)
Less than 6 months	37.8	-	-
6 to less than 12 months	12.5	-	-
12 to less than 18 months	7.8	-	-
18 to less than 24 months	15.3	-	-
24 months or more	26.7	-	-

SOURCE: Authors’ analysis

^†Note 1: For zip code in which practice is located

^¥Note 2: As of December 31, 2010

^*Note 3: p<.05 for test of difference between PCIP physicians and all comparison physicians

^ΨNote 3: p<.05 for test of difference between PCIP physicians and matched comparison physicians