Medicare Program; Medicare Shared Savings Program; Accountable Care Organizations--Revised Benchmark Rebasing Methodology, Facilitating Transition to Performance-Based Risk, and Administrative Finality of Financial Calculations. Final rule.

Under the Medicare Shared Savings Program (Shared Savings Program), providers of services and suppliers that participate in an Accountable Care Organization (ACO) continue to receive traditional Medicare fee-for-service (FFS) payments under Parts A and B, but the ACO may be eligible to receive a shared savings payment if it meets specified quality and savings requirements. This final rule addresses changes to the Shared Savings Program, including: Modifications to the program's benchmarking methodology, when resetting (rebasing) the ACO's benchmark for a second or subsequent agreement period, to encourage ACOs' continued investment in care coordination and quality improvement; an alternative participation option to encourage ACOs to enter performance-based risk arrangements earlier in their participation under the program; and policies for reopening of payment determinations to make corrections after financial calculations have been performed and ACO shared savings and shared losses for a performance year have been determined.