Beneficiary Experience, Affordability, Utilization, and Quality in Medicare Advantage and Traditional Medicare: A Review of the Literature

The growing role of Medicare Advantage in the Medicare program and the changing demographics of Medicare Advantage enrollees have given rise to an interest in how well private plans serve their enrollees relative to traditional Medicare. To answer this question, we build on a previous review of research by examining 62 studies published since 2016 that compare Medicare Advantage and traditional Medicare based on measures of beneficiary experience, affordability, service utilization, and quality.

We found few differences between Medicare Advantage and traditional Medicare that are supported by strong evidence or have been replicated across multiple studies. Both Medicare Advantage and traditional Medicare beneficiaries reported similar rates of satisfaction with their care and overall measures of care coordination. Medicare Advantage outperformed traditional Medicare on some measures, such as use of preventive services, having a usual source of care, and lower hospital readmission rates. However, traditional Medicare outperformed Medicare Advantage on other 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. Additionally, 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. Several studies found lower use of post-acute care among Medicare Advantage enrollees but were inconclusive as to whether that was associated with better or worse outcomes. 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.

When possible, we highlight findings for specific subgroups of interest, such as beneficiaries from communities of color, living in rural areas, or dually eligible for Medicare and Medicaid. Notably, relatively few studies specifically examine these population subgroups, so it is difficult to assess the strength of the findings or how broadly they apply. For example, one study found that Black Medicare beneficiaries had higher rates of potentially avoidable hospitalizations in Medicare Advantage than in traditional Medicare. While important, we could not identify additional analyses that compared the rate of potentially avoidable hospitalizations between Medicare Advantage and traditional Medicare among Hispanic and other beneficiaries of color, beneficiaries living in rural areas, or beneficiaries dually eligible for Medicare and Medicaid. Additionally, despite an increased focus on alternative payment models in Medicare, we only identified two studies that differentiated traditional Medicare beneficiaries attributed to accountable care organizations (ACOs) from traditional Medicare beneficiaries not attributed to ACOs.

Our findings across all measures are summarized below.

Beneficiary Experience

Satisfaction, access to care, care coordination, and experience with prescription drugs: Beneficiaries in Medicare Advantage and traditional Medicare reported similar rates of satisfaction with their care, and similar experiences with wait times, finding a new provider, and overall measures of care coordination. However, Medicare Advantage enrollees were more likely to report having a usual source of care, receiving information during care transitions, and having better experiences getting needed prescription drugs.

Switching: Overall, there were low rates of switching between Medicare Advantage and traditional Medicare, though a slightly larger share of Medicare Advantage enrollees opted to switch from Medicare Advantage to traditional Medicare than beneficiaries who switched from traditional Medicare to Medicare Advantage. Additionally, rates of switching from Medicare Advantage to traditional Medicare were relatively higher among beneficiaries who are dually eligible for Medicare and Medicaid, beneficiaries of color, beneficiaries in rural areas, and following the onset of a functional impairment. Switching rates may be a proxy for dissatisfaction with current coverage arrangements.

Affordability

A somewhat smaller share of beneficiaries in traditional Medicare with supplemental coverage than Medicare Advantage enrollees reported having cost-related problems. Similar findings were observed among Black beneficiaries, beneficiaries under the age of 65, and beneficiaries in fair or poor self-assessed health. Beneficiaries in traditional Medicare with no supplemental coverage had higher rates of cost-related problems than beneficiaries enrolled in Medicare Advantage plans. Three studies examining beneficiaries with high-needs, diabetes, or a mental illness found no differences in affordability-related measures between Medicare Advantage and traditional Medicare.

Utilization

Preventive services: Medicare Advantage enrollees were more likely than beneficiaries in traditional Medicare to receive preventive care services, such as annual wellness visits and routine checkups, screenings, and flu or pneumococcal vaccines, based on several studies, with similar findings for people of color and beneficiaries under age 65.

Hospital Services: Differences in the use of hospital services between people in Medicare Advantage and traditional Medicare varied based on how hospital utilization is measured. Overall, there were generally no differences in the aggregate number of hospital days or average length of stay for common medical admissions, based on evidence from five studies. Four studies found fewer hospital stays among Medicare Advantage enrollees compared to traditional Medicare beneficiaries for at least some groups of beneficiaries. Differences in the share of beneficiaries with at least one hospital stay varied, with two studies finding no differences between Medicare Advantage and traditional Medicare and two studies finding lower rates in Medicare Advantage. No studies examined differences in hospital utilization between Medicare Advantage and traditional Medicare by race and ethnicity or other demographics.

Post-Acute Care: Several studies reported lower rates of skilled nursing facility (SNF), inpatient rehabilitation facility (IRF), and home health use among Medicare Advantage enrollees, and shorter lengths of stay in SNFs and IRFs for Medicare Advantage enrollees than traditional Medicare beneficiaries. Across the seven studies that examined the relationship between post-acute care use, home health use, and patient outcomes, studies generally found lower hospital readmission rates among Medicare advantage users of SNFs and lower hospitalization rates among Medicare Advantage users of home health, but mixed results across other outcomes of care. None of these studies presented results by race and ethnicity or other demographics.

Prescription Drugs: Findings on prescription drug use varied depending on the measure of utilization and condition studied. Three studies found that among specific groups – people with a mental illness, diabetes, Alzheimer’s disease, and high-need beneficiaries (each studied separately) – there were no differences in the use of prescription drugs between Medicare Advantage and traditional Medicare beneficiaries. Two of these studies found that the use of prescription drugs was higher for Medicare Advantage enrollees than traditional Medicare beneficiaries without diabetes and without Alzheimer’s disease. Conversely, another study found that Medicare Advantage enrollees were less likely than traditional Medicare beneficiaries in stand-alone prescription drug plans to fill at least one prescription for an opioid. None of these studies stratified results by race and ethnicity or other demographic groups.

Physician-administered drugs (i.e., Part B drugs): A single study examined the use of physician-administered drugs and found no difference between Medicare Advantage enrollees and traditional Medicare beneficiaries in the number of injectable drug procedures. Another study found that Medicare Advantage enrollees were more likely than traditional Medicare beneficiaries to receive low-cost Part B drugs in four clinical scenarios where similar or equally effective drugs exist, suggesting that Medicare Advantage coverage may be associated with more efficient prescribing of Part B drugs. These two studies did not present results by race, ethnicity, or other demographics.

Other medical provider and emergency department visits: Medicare Advantage enrollees had fewer medical provider visits overall, but more primary care visits per person, based on four of the six studies we reviewed that compared the number of provider visits between beneficiaries enrolled in Medicare Advantage and traditional Medicare. Emergency department (ED) use was generally similar among Medicare Advantage and traditional Medicare beneficiaries overall, based on one study. A second study that focused on beneficiaries in a single hospital-based delivery system (Banner Health) found that Medicare Advantage enrollees had higher ED visit rates than traditional Medicare attributed to an ACO and traditional Medicare beneficiaries not attributed to an ACO. None of these studies presented results by race, ethnicity, or other demographics.

Quality

Hospital Readmissions: Seven of the 12 studies comparing hospital readmission rates found lower overall readmission rates among Medicare Advantage enrollees than among traditional Medicare beneficiaries. However, four studies that were limited to beneficiaries in a single hospital or beneficiaries undergoing specific procedures, such as knee/hip replacements, found no differences. One study that looked at readmission rates for people with three chronic conditions (myocardial infarction, congestive heart failure, and pneumonia) found higher readmission rates among Medicare Advantage enrollees relative to beneficiaries in traditional Medicare. In two separate studies, Black beneficiaries had higher readmission rates than White beneficiaries in both Medicare Advantage and traditional Medicare.

Potentially avoidable hospitalizations: One study found that Black beneficiaries had higher rates of potentially avoidable hospitalizations for ambulatory care sensitive conditions (ACSCs) in Medicare Advantage than in traditional Medicare. Another study examined rates of hospitalization for ambulatory care sensitive conditions overall and by clinical condition, finding that traditional Medicare beneficiaries were hospitalized more often than Medicare Advantage enrollees for ACSCs; however, this study did not account for differences in the characteristics of Medicare Advantage enrollees and traditional Medicare beneficiaries.

Quality of facility or provider: Five of six studies we reviewed that looked at quality ratings of health care facilities and providers used by Medicare Advantage enrollees and traditional Medicare beneficiaries found that Medicare Advantage enrollees were less likely than traditional Medicare beneficiaries to receive care in the highest-or lowest-rated hospitals overall or in the highest-rated hospitals for cancer care, skilled nursing facilities (SNFs), and home health agencies. A sixth study examined 18 facility-level quality measures in long-stay nursing homes (i.e., nursing homes) and short-stay nursing homes (i.e., SNFs), finding no differences between Medicare Advantage and traditional Medicare for ten of the measures. However, the remaining eight measures had mixed findings, with Medicare Advantage enrollees having lower risk of antipsychotic drug use while traditional Medicare beneficiaries having lower risk of moderate to severe pain and urinary incontinence.

Disease management (heart disease and diabetes): Findings on disease management varied by condition and quality measure. Among beneficiaries with heart disease, Medicare Advantage enrollees were more likely than those in traditional Medicare to receive guideline-recommended therapies in ambulatory settings, but there were no differences reported in inpatient settings. Additionally, among people with diabetes, Medicare Advantage enrollees were more likely than beneficiaries in traditional Medicare to be prescribed guideline-recommended therapy, use medication for their condition, and perform better on clinical care measures such as diabetic eye exam screening; however, there were no differences in blood sugar control, insulin use, or receipt of blood diabetes tests between Medicare Advantage enrollees and traditional Medicare beneficiaries.