Comparison of Low-Value Services Among Medicare Advantage and Traditional Medicare Beneficiaries.

Importance: Low-value care in the Medicare program is prevalent, costly, potentially harmful, and persistent. Although Medicare Advantage (MA) plans can use managed care strategies not available in traditional Medicare (TM), it is not clear whether this flexibility is associated with lower rates of low-value care. Objectives: To compare rates of low-value services between MA and TM beneficiaries and explore how elements of insurance design present in MA are associated with the delivery of low-value care. Design, Setting, and Participants: This cross-sectional study analyzed beneficiaries enrolled in MA and TM using claims data from a large, national MA insurer and a random 5% sample of TM beneficiaries. The study period was January 1, 2017, through December 31, 2019. All analyses were conducted from July 2021 to March 2022. Exposures: Enrollment in MA vs TM. Main Outcomes and Measures: Low-value care was assessed using 26 claims-based measures. Regression models were used to estimate the association between MA enrollment and rates of low-value services while controlling for beneficiary characteristics. Stratified analyses explored whether network design, product design, value-based payment, or utilization management moderated differences in low-value care between MA and TM beneficiaries and among MA beneficiaries. Results: Among a study population of 2 470 199 Medicare beneficiaries (mean [SD] age, 75.6 [7.0] years; 1 346 777 [54.5%] female; 229 107 [9.3%] Black and 2 126 353 [86.1%] White individuals), 1 527 763 (61.8%) were enrolled in MA and 942 436 (38.2%) were enrolled in TM. Beneficiaries enrolled in MA received 9.2% (95% CI, 8.5%-9.8%) fewer low-value services in 2019 than TM beneficiaries (23.1 vs 25.4 total low-value services per 100 beneficiaries). Although MA beneficiaries enrolled in health management organization and preferred provider organization products received fewer low-value services than TM beneficiaries, the difference was largest for those enrolled in health management organization products (2.6 fewer [95% CI, 2.4-2.8] vs 2.1 fewer [95% CI, 1.9-2.3] services per 100 beneficiaries, respectively). Across primary care payment arrangements, MA beneficiaries received fewer low-value services than TM beneficiaries, with the largest difference observed for MA beneficiaries whose primary care physicians were reimbursed within 2-sided risk arrangements. Conclusions and Relevance: In this cross-sectional study of Medicare beneficiaries, those enrolled in MA had lower rates of low-value care than those enrolled in TM; elements of insurance design present in the MA program and absent in TM were associated with reduction in low-value care.