Of the 45 million Medicare beneficiaries, 19 percent are enrolled in a Medicare Advantage health plan. The other 81 percent choose to remain in traditional fee-for-service Medicare for Part A and Part B services. Governed under Part C of Medicare, Medicare Advantage health plans come in several flavors, most notably HMOs, PPOs, special needs plans (SNPs), and private fee-for-service plans.

While only about 16% of Medicare Advantage enrollees and about 3 percent of all Medicare beneficiaries are in private fee-for-service plans, these PFFS plans are receiving considerable attention by Congress and Wall Street. To help you understand the unusual dynamics at play, here are some helpful resources:

An Examination of Medicare Private Fee-for-Service Plans: This paper by Jonathan Blum, et al from Avalere Health, covers the history, features, trends, and policy and market implications of PFFS plans.

The Medicare Advantage Program: Trends and Options: Congressional Budget Office (CBO) report, with CBO’s projections for Medicare managed care enrollment.

Private Fee-For-Service Plans in Medicare Advantage: Testimony by Mark E. Miller, Ph.D., executive director of the Medicare Payment Advisory Commission (MedPAC) on MedPAC’s observations and recommendations.

Private Fee-For-Service Plans In Medicare: Rapid Growth and Future Implications: In testimony before the House Ways and Means Committee, Patricia Neuman, Ph.D, a Kaiser Family Foundation vice president, offered a thoughtful overview of many of the key issues.

The Impact of Reductions in Medicare Advantage Funding on Beneficiaries: This study, by Adam J. Atherly, Ph.D. and Kenneth E. Thorpe, Ph.D. of Emory University, shows financial savings Medicare Advantage enrollees receive and therefore the adverse impact on benies of proposed cuts to Medicare Advantage plans.

Medicare Advantage Program Payment System: An excellent 4-page primer by MedPAC on how CMS sets Medicare Advantage plan payments.