This brief explores the interplay of Medicare Advantage (MA) enrollment and beneficiary attribution to Centers for Medicare & Medicaid Services (CMS) Medicare Shared Savings Program (MSSP) Accountable Care Organizations (ACO).
MA enrollees are not eligible for such ACO attribution, and both payment models are drawn from the same pool of Medicare beneficiaries. As the number of beneficiaries not participating in either is shrinking, it is important to understand how the growth (or shrinkage) in one model influences participation in the other.