§ 425.604 Calculation of savings under the one-sided model.

(a) Savings determination. For each performance year, CMS determines whether the estimated average per capita Medicare expenditures under the ACO for Medicare fee-for-service beneficiaries for Parts A and B services are below the applicable updated benchmark determined under § 425.602 or § 425.603.

(1) Newly assigned beneficiaries. CMS uses an ACO's HCC prospective risk score to adjust the benchmark for changes in severity and case mix in this population.

(2) Continuously assigned beneficiaries. (i) CMS uses demographic factors to adjust the benchmark for changes in the continuously assigned population.

(ii) If the prospective HCC risk score is lower in the performance year for this population, CMS will adjust the benchmark for changes in severity and case mix in this population using this lower prospective HCC risk score.

(3) Assigned beneficiary changes in demographics and health status are used to adjust benchmark expenditures as described in § 425.602(a) or § 425.603(c). In adjusting the benchmark for health status and demographic changes CMS makes adjustments for separate categories for each of the following populations of beneficiaries:

(i) ESRD.

(ii) Disabled.

(iii) Aged/dual eligible Medicare and Medicaid beneficiaries.