In health care, vertical integration—common ownership of producers of complementary services—may have both pro- and anticompetitive effects. We use data on 40 million commercially insured individuals from the Health Care Cost Institute to construct price indices for office visits to general practice and specialist physicians for the years 2008–12. Controlling for generalist market concentration, we find that generalists charge higher prices when they are integrated with specialists, and that the effect of integration is larger in more concentrated specialist markets. Conversely, controlling for specialist market concentration, specialists charge higher prices when integrated with generalists, with larger effects in more concentrated generalist markets. Our results suggest that multispecialty practice enhances physician market power.

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多种专科实践会增强医师的市场力量吗？

在医疗保健领域，纵向整合（互补服务生产者的共有所有权）可能同时具有正面和反竞争的作用。我们使用来自医疗保健成本研究所的4000万商业保险个人的数据来构建2008-12年度普通科和专科医生就诊的价格指数。通过控制通才市场的集中度，我们发现通才与专家集成时会收取更高的价格，而集成在更集中的专家市场中的影响更大。相反，为了控制专家市场的集中度，专家与通才整合时会收取更高的价格，在更集中的通才市场中产生更大的影响。我们的结果表明，多专业实践可以增强医师的市场力量。