Econometrica · 2017 · Kate Ho、Robin S. Lee
中文摘要
保险公司竞争对美国私营医疗保健行业中福利、议定的医疗服务提供者价格以及保费的影响在理论上是不确定的。竞争减弱可能提高保险公司收取的保费及其向医院支付的费用。然而，它也可能增强保险公司与医院谈判时的议价筹码，从而产生可抵消的成本下降。为理解和衡量这一权衡，我们利用详细的加利福尼亚州入院、理赔与参保数据，估计了一个包含雇主—保险公司与医院—保险公司就保费和医疗费用偿付进行议价、家庭保险需求以及个人医院需求的模型。我们模拟了将大型和小型保险公司从消费者选择集中移除的情形。尽管消费者福利下降且保费通常上升，但我们发现，如果雇主通过与其余保险公司的谈判施加有效的保费约束，那么在移除一家小型保险公司后保费可能下降。我们还记录到医院价格调整在移除一家保险公司后存在较大异质性，各市场重新议定的价格涨跌幅高达10%。
Abstract
The impact of insurer competition on welfare, negotiated provider prices, and premiums in the U.S. private health care industry is theoretically ambiguous.Reduced competition may increase the premiums charged by insurers and their payments made to hospitals.However, it may also strengthen insurers' bargaining leverage when negotiating with hospitals, thereby generating offsetting cost decreases.To understand and measure this trade-off, we estimate a model of employer-insurer and hospital-insurer bargaining over premiums and reimbursements, household demand for insurance, and individual demand for hospitals using detailed California admissions, claims, and enrollment data.We simulate the removal of both large and small insurers from consumers' choice sets.Although consumer welfare decreases and premiums typically increase, we find that premiums can fall upon the removal of a small insurer if an employer imposes effective premium constraints through negotiations with the remaining insurers.We also document substantial heterogeneity in hospital price adjustments upon the removal of an insurer, with renegotiated price increases and decreases of as much as 10% across markets.