The Effects of Medicare Advantage on Healthcare Use and Patient Outcomes

项目总结/摘要 越来越多的医疗保险受益人参加了医疗保险优势（MA），而不是传统的费用- 医疗服务（TM）医疗保险，MA份额从2004年的13%增加到2020年的39%。中心的 医疗保险和医疗补助服务（CMS）支付MA计划每月资本率，以涵盖几乎所有的医疗保健 计划参加者的费用。MA计划将不用于覆盖注册者的付款部分作为利润 费用此外，CMS赠款MA计划更大的自由来管理注册者的医疗保健使用，例如， 通过工具，如狭窄的供应商网络和更广泛的交付创新， 远程医疗支持者认为，这些财务激励措施和有效的千年评估计划工具可能会使 他们提供比TM更有效的护理。另一方面，这些影响可以通过金融手段来抵消。 在按人头收费的激励下，将服务提供限制在改善短期健康所必需的范围之外， 对长期结果产生不利影响。以前的工作主要是估计横截面 TM和MA入组者的比较，如果MA入组者与TM不同，则可能导致偏倚估计 参与者以其他方式与医疗保健使用和健康结果相关。我们的项目将研究 来自七个州的MA入学率的变化，这些州最近改变了公共退休人员的健康福利， 强制性MA计划的补充TM覆盖范围（或在一个州，从强制性MA计划到补充 TM覆盖率）。我们将使用这些自然实验，沿着TM和MA的综合医疗数据 入组者，以估计MA入组对医疗保健使用、质量和患者结局的因果影响。 这些结果将为决策者提供重要证据，以权衡医疗保险的更广泛扩张 优势

Project Summary/ Abstract A growing share of Medicare beneficiaries are enrolled in Medicare Advantage (MA) rather than traditional fee- for-service (TM) Medicare, with the MA share increasing from 13% in 2004 to 39% in 2020. The Centers for Medicare and Medicaid Services (CMS) pay MA plans a monthly capitated rate to cover nearly all health care expenses for plan enrollees. MA plans keep as profits the portion of payments that are not used to cover enrollee expenses. In addition, CMS grants MA plans greater freedom to manage enrollees’ health care use, for example, through tools such as narrow provider networks and broader coverage of delivery innovations such as telemedicine. Proponents argue that these financial incentives and effective tools for MA plans might enable them to provide care more efficiently than TM. On the other hand, these effects could be offset by financial incentives under capitation to limit service provision beyond what is necessary to improve short term health, resulting in adverse impacts on longer-term outcomes. Prior work has primarily estimated cross-sectional comparisons of TM and MA enrollees, which could lead to biased estimates if MA enrollees differ from TM enrollees in other ways that are related to health care use and health outcomes. Our proposed project will study changes in MA enrollment coming from seven states that recently changed public retiree health benefits from supplemental TM coverage to mandatory MA plans (or in one state, from a mandatory MA plan to supplemental TM coverage). We will use these natural experiments, along with comprehensive Medicare data for TM and MA enrollees, to estimate the causal impact of MA enrollment on health care use, quality, and patient outcomes. These results will provide important evidence to policymakers weighing broader expansions of Medicare Advantage.