Appendix Table 3.

Organizational Characteristics

Number	Region	Organization Type^{^*}	Composition	Ownership^{^**}	Rurality^{^***}
1	West	Practice (Federally qualified health center (FQHC))	1 practice	Independent	Rural
2	West	Multi-practice physician organization, including FQHCs	<10 practices	Independent	Rural
3	West	System, includes FQHCs	<10 practices	Not applicable	Urban
4	Northeast	System	10 to 50 practices	Not applicable	Urban, suburban
5	West	System	<10 hospitals, >100 practices	Not applicable	Mix
6	South	System	10 to 50 practices	Not applicable	Mix, largely rural
7	Northeast	Practice	1 practice	System	Rural
8	Northeast	System including critical access hospitals (CAHs)	>10 hospitals, >100 practices	Not applicable	Mix
9	South	System, includes CAHs and FQHCs	>10 hospitals, >100 practices	Not applicable	Mix
10	Northeast	Multi-practice physician organization, including FQHC	<10 practices	Independent	Rural
11	West	System	<10 hospitals, 10 to 50 practices	Not applicable	Mix
12	West	System	<10 hospitals, 10 to 50 practices	Not applicable	Urban
13	South	System	<10 hospitals, >10 practices	Not applicable	Mix
14	Midwest	Multi-practice physician organization	<10 practices	Independent	Suburban
15	Northeast	System, includes FQHC	<10 hospitals, 50 to 100 practices	Not applicable	Urban
16	Midwest	System, includes a CAH	<10 hospitals, 50 to 100 practices	Not applicable	Mix
17	Northeast	System	<10 hospitals, >100 practices	Not applicable	Urban, suburban

↵* For practices and multi-site physician organizations, we noted if they were an FQHC. For systems, we noted if the system included FQHCs or CAHs, but this not a focus area of our interviews.
↵** We only included ownership for practices. None of the included systems were federally owned.
↵*** Many systems covered large geographic areas and includes practices in a mix of rural, suburban, and urban areas.