A Review of 62 Studies Finds Few Big Differences Between Traditional Medicare and Medicare Advantage on a Variety of Measures

With the Medicare open enrollment period set to begin Oct. 15, a perennial decision faced by Medicare beneficiaries is whether to get their coverage through traditional Medicare or the private plans known as Medicare Advantage.

A new KFF review of 62 studies published since 2016 that compares Medicare Advantage and traditional Medicare on measures of beneficiary experience, affordability, utilization, and quality finds few differences that are supported by strong evidence or have been replicated across multiple studies. For example, beneficiaries in both coverage types reported similar rates of satisfaction with their care and overall measures of care coordination.

Notably, relatively few studies specifically examined specific subgroups of interest, such as beneficiaries from communities of color, living in rural areas, or dually eligible for Medicare and Medicaid, making it difficult to assess the strength of the findings or how broadly they apply.

In some areas, however, the research identified noteworthy differences between Medicare Advantage and traditional Medicare, including: 

Medicare Advantage:

• Medicare Advantage enrollees were more likely than those in traditional Medicare to report having a usual source of care. They were also more likely to receive preventive care services, such as annual wellness visits and routine checkups, screenings, and flu or pneumococcal vaccines.
• Medicare Advantage enrollees reported better experiences getting needed prescription drugs than traditional Medicare beneficiaries overall. However, among beneficiaries with diabetes, cancer, or a mental health condition, findings were mixed.
• Most studies found that utilization of home health services and post-acute skilled nursing or inpatient rehabilitation facility care was lower among Medicare Advantage enrollees than traditional Medicare beneficiaries, but were inconclusive as to whether that was associated with better or worse outcomes.

Traditional Medicare:

• A somewhat smaller share of traditional Medicare beneficiaries than Medicare Advantage enrollees experienced a cost-related problem, mainly due to lower rates of cost-related problems among traditional Medicare beneficiaries with supplemental coverage. (But traditional Medicare beneficiaries without supplemental coverage had the most affordability-related difficulties.)
• Traditional Medicare outperformed Medicare Advantage on measures such as receiving care in the highest-rated hospitals for cancer care or in the highest-quality skilled nursing facilities and home health agencies.

In other areas, though, findings were mixed or showed little difference between Medicare Advantage and traditional Medicare based on multiple studies.

Among the findings:

• There were generally no differences in the aggregate number of hospital days or average length of stay for common medical admissions.
• Neither Medicare Advantage nor traditional Medicare consistently performed better across all quality measures.
• Additionally, two analyses of several measures of beneficiary experience found no differences between the two groups in experiences with wait times and in the share reporting trouble finding a general doctor, being told that their health insurance was not accepted, and being told they would not be accepted as a new patient.

Findings related to the use of other health care services, including hospital care and prescription drugs, and condition-specific quality of care measures varied – likely due to differences in data and methodology across studies.

Interest in how well Medicare Advantage plans serve their growing and increasingly diverse enrollee population has never been higher, as Medicare Advantage, for the first time, is projected to enroll more than half of all eligible Medicare beneficiaries next year, making it the main way that Medicare beneficiaries get their coverage and care. In comparison, just over a decade ago in 2010, 25 percent of the eligible population was in a Medicare Advantage plan.

The Medicare open enrollment period runs through Dec. 7.

The full analysis, Beneficiary Experience, Affordability, Utilization, and Quality in Medicare Advantage and Traditional Medicare: A Review of the Literature, as well as more data and analyses about Medicare Advantage, are available at kff.org.