EXHIBIT 3.

Variation In Differences In Patients’ General Health And Mental Health Between Accountable Care Organization (ACO) And Non-ACO Providers in Local Service Areas

	Patient characteristics included in model	Mean percent in poorer health	ACO-level variation in health difference versus local non-ACO providers	Expected distribution of health differences among ACOs
				(Percentile)
			Standard deviation (percentage point)	10th	25th	75th	90th
General health status	Demographic	29	2.6	−3.3	−1.8	1.8	3.3
	Demographic and HCC		2.4	−3.1	−1.6	1.6	3.1
Mental health status	Demographic	35	1.4	−1.8	−0.9	0.9	1.8
	Demographic and HCC		1.4	−1.8	−0.9	0.9	1.8

SOURCE Authors’ analyses of data from the Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey of fee-for-service Medicare beneficiaries and linked Medicare claims, 2011–12. NOTES For general health status, the poorer health category was “fair” and “poor.” For mental health status, this category included “good,” “fair,” and “poor.” Standard deviations were estimated using multilevel regression models. Expected values for percentiles in the ACO distribution of health differences were calculated based on the estimated standard deviations, assuming a normal distribution and using the mean differences in health status for patients attributed to ACOs and those attributed to non-ACO providers (which were close to zero). HCC is Hierarchical Condition Category.