Managed Care, Consolidation among Health Care Providers, and Health Care: Evidence from Mammography
研究管理式医疗如何影响医疗服务提供者的市场结构，发现健康维护组织（HMO）市场份额增加会导致乳腺X光检查提供者数量减少、单个提供者服务量增加、成本下降但等待时间延长，而健康结果未恶化。
We discuss the effects of managed care on the structure of the health care delivery system, focusing on managed-care-induced consolidation among health care providers. We empirically investigate the relationship between HMO market share and mammography providers. We find evidence of consolidation: increases in HMO activity are associated with reductions in the number of mammography providers and with increases in the number of services produced by remaining providers. We also find that increases in HMO market share are associated with reductions in costs for mammography and with increases in waiting times for appointments, but not with worse health outcomes.