Hospital Network Competition and Adverse Selection: Evidence from the Massachusetts Health Insurance Exchange
中文摘要
健康保险公司日益在其医疗服务提供者网络上展开竞争。利用马萨诸塞州保险交易所的数据，我发现针对覆盖最负盛名且最昂贵的“明星”医院的计划存在显著的逆向选择。我强调了一个理论上独特的筛选渠道：忠诚于明星医院的消费者，在给定其医疗状况的条件下，会产生高额支出，因为他们使用了这些医院昂贵的医疗服务。这意味着消费者为获得明星医院准入而付出的增量成本存在异质性，对标准的筛选政策构成了挑战。除了对未观察到的疾病严重程度的筛选外，我发现这产生了强烈的排除明星医院的激励，即使有风险调整措施。(JEL D82, G22, H75, I11, I13, I18)
Abstract
Health insurers increasingly compete on their networks of medical providers. Using data from Massachusetts’s insurance exchange, I find substantial adverse selection against plans covering the most prestigious and expensive “star” hospitals. I highlight a theoretically distinct selection channel: consumers loyal to star hospitals incur high spending, conditional on their medical state, because they use these hospitals’ expensive care. This implies heterogeneity in consumers’ incremental costs of gaining access to star hospitals, posing a challenge for standard selection policies. Along with selection on unobserved sickness, I find this creates strong incentives to exclude star hospitals, even with risk adjustment in place. (JEL D82, G22, H75, I11, I13, I18)