Enrolling in a higher-cost Medicare Advantage (MA) plan may not always provide seniors with better-quality health care, according to a new RAND Corporation study, which took a retrospective look at quality measures among plans in 2016 and 2017.

Researchers examined 15 different measures of quality among large representative samples of people enrolled in MA plans during 2016 and 2017. They found that plans that charged a higher monthly premium provided on average only slightly better care as compared to plans with no monthly premium.

Quality varied substantially within each premium cost tier studied, with high-quality care being observed among a number of plans in each of the cost tiers. More than 700 MA plans were part of the analysis.

The findings were published in the latest edition of JAMA Health Forum.

“Paying higher premiums is not necessary to receive high-quality care from a Medicare Advantage plan,” said study lead author Amelia M. Haviland, a professor of statistics and public policy at Carnegie Mellon University and an adjunct statistician at RAND, a nonprofit research organization, in the study announcement. “Seniors should look at metrics other than premium costs alone when looking for a Medicare Advantage plan that offers a high quality of care, including direct measures of quality, such as Star ratings.”

Health care costs are a concern for both consumers and policymakers. People enrolled in MA plans report that price measures such as premium costs and copays are their primary consideration when selecting a plan.

But the findings conflict with a recent report from the Better Medicare Alliance, which found that the average monthly premium for MA plans in 2022 is $19, a 15-year low. MA members also reported they spent nearly $2,000 less on out-of-pocket costs and premiums annually.

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To examine the link between premium cost and quality, RAND researchers analyzed information about the care delivered to people enrolled in MA plans. About 40 percent of the enrollees were in plans with no monthly premium, while 6 percent were in plans with a monthly premium of more than $120.

MA plans provide coverage for hospital and physician services like traditional Medicare fee-for-service, but typically also offer additional services such as coverage for dental care and eyeglasses. In exchange for additional services and lower copays, members are restricted to in-network providers. In 2022, nearly half of eligible Medicare beneficiaries are now enrolled in MA plans.

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The information that RAND used to measure the quality of care from MA plans included clinical quality measures based on administrative information such as medical charts involving more than two million enrollees. Those quality measures included items such as whether patients received recommended cancer screenings, whether high blood pressure was controlled, and whether diabetes was treated adequately.

The study also included surveys of more than 168,000 MA members who were asked about their experiences with health care, prescription drug coverage, and their plan. Those measures included the ability to get care, the ability to get care quickly, and getting needed drugs.

Across most measures, people enrolled in the two higher-premium plan tiers reported similar or slightly better experiences on average than enrollees in the lower-premium categories. For example, people enrolled in the highest-premium tiers were more likely to receive annual flu shots.

However, on one measure, lower-cost plans offered better care. People enrolled in lower-tiered plans received better care on average for osteoporosis than their peers enrolled in higher-premium plans.

“Given that many high- and low-quality plans were found in each of the premium tiers we studied, the premium cost is a poor proxy for assessing the quality of a Medicare Advantage plan,” Haviland said. “Making plan quality information more accessible and salient to consumers is a key to reducing consumers' costs while improving quality.”