Cabral Marika, Mahoney Neale
University of Texas Austin, 1 University Station BRB 1.116, C3100 Austin, TX 78712, and NBER.
Chicago Booth, 5807 S. Woodlawn Ave. Chicago, IL 60637, and NBER.
Am Econ J Appl Econ. 2019 Apr;11(2):37-73. doi: 10.1257/app.20160350.
Most health insurance uses cost-sharing to reduce excess utilization. Supplemental insurance can blunt the impact of this cost-sharing, increasing utilization and exerting a negative externality on the primary insurer. This paper estimates the effect of private Medigap supplemental insurance on public Medicare spending using Medigap premium discontinuities in local medical markets that span state boundaries. Using administrative data on the universe of Medicare beneficiaries, we estimate that Medigap increases an individual's Medicare spending by 22.2 percent. We calculate that a 15 percent tax on Medigap premiums generates savings of $12.9 billion annually with a standard error of $4.9 billion.
大多数医疗保险采用成本分摊来减少过度使用。补充保险会削弱这种成本分摊的影响，增加使用量，并对主要保险公司产生负面外部效应。本文利用跨越州界的当地医疗市场中补充医保（Medigap）保费的不连续性，估计了私人补充医保对公共医疗保险支出的影响。利用医疗保险受益人的全部行政数据，我们估计补充医保会使个人的医疗保险支出增加22.2%。我们计算得出，对补充医保保费征收15%的税，每年可节省129亿美元，标准误差为49亿美元。
