50-character summary: Half of Medicare Advantage members switch plans within 5 years; returning to Original Medicare may be difficult.

400-character summary: A Brown University School of Public Health study found that about half of Medicare Advantage members left their plans within five years, often switching to another Medicare Advantage plan. Returning to Original Medicare can be difficult due to limited access to Medigap plans. For those with serious health conditions, Medicare Advantage's limited provider networks and prior authorization requirements may hinder access to necessary care.