Changes in the way health insurers pay healthcare providers may not only directly affect the insurer’s patients but may also affect patients covered by other insurers. We provide evidence of such spillovers in the context of a nationwide Medicare bundled payment reform that was implemented in some areas of the country but not in others, via random assignment. We estimate that the payment reform—which targeted traditional Medicare patients—had effects of similar magnitude on the healthcare experience of nontargeted, privately insured Medicare Advantage patients. We discuss the implications of these findings for estimates of the impact of healthcare payment reforms and more generally for the design of healthcare policy.

健康保险公司向医疗保健提供者付款方式的变化不仅可能直接影响保险公司的患者，还可能影响其他保险公司承保的患者。我们通过随机分配在全国范围内的医疗保险捆绑支付改革的背景下提供了这种溢出效应的证据，该改革在该国的一些地区实施，但在其他地区则没有实施。我们估计，针对传统医疗保险患者的支付改革对非目标、私人保险医疗保险优惠患者的医疗保健体验产生了类似程度的影响。我们讨论这些发现对医疗支付改革影响的估计以及更广泛的医疗政策设计的影响。