Table 5.

Ordinary Least Squares Analysis: The Relationship between Hospital–Physician Affiliations and AMI Patient Treatments, Payments, and Outcomes, 1994–1998

		Dependent Variables
	Independent Variable: Affiliation Type	Catheter within 90 Days	PTCA or CABG within 90 Days	Log 90-Day Inpatient Payments	AMI Readmit within 90 Days	90-Day Mortality
Model 1	Any	.14	.12	.35	−.10	.33
		(.26)	(.25)	(.34)	(.06)	(.19)
Model 2	Low	−.04	.14	.01	−.06	.13
		(.24)	(.24)	(.34)	(.06)	(.18)
	High	.17	.09	.38	−.07	.12
		(.21)	(.21)	(.28)	(.05)	(.15)
Model 3	IPA	.25	.44	.41	−.02	−.03
		(.25)	(.24)	(.37)	(.06)	(.19)
	PHO	.03	.22	−.04	−.05	−.13
		(.26)	(.25)	(.37)	(.06)	(.19)
	MSO	−.22	−.21	−.50	−.12*	.14
		(.24)	(.23)	(.31)	(.05)	(.17)
	ISM	.68*	.62*	.86*	.07	.07
		(.25)	(.24)	(.36)	(.06)	(.18)
	Foundation	.30	.31	.62	−.10	.21
		(.28)	(.28)	(.40)	(.07)	(.20)
	Equity	.02	−.34	−.18	.14	.09
		(.43)	(.44)	(.68)	(.11)	(.33)
	GPWW	−.09	.15	−.34	−.10	−.11
		(.30)	(.31)	(.46)	(.08)	(.25)

Notes: Regressions also include hospital traits, patient traits, market traits, hospital fixed effects, and year fixed effects; full results reported in Appendix. Coefficients and robust standard errors (in parentheses) reported in percentage points. Stata cluster function used to correct for lack of independence across observations for patients admitted to the same hospital. AMI = acute myocardial infarction; PTCA = percutaneous transluminal coronary angioplasty; CABG = coronary artery bypass graft; IPA = independent practice association; PHO = physician–hospital organization; MSO = management services organization; ISM = integrated salary model; GPWW = group practice without walls.

^*Significant at p<.05 level.