We use administrative data from Medicare to document the massive consolidation of primary care physicians over the last decade and its impact on patient healthcare utilization. We first document that primary care organizations have consolidated all over the United States between 2008 and 2014. We then show that regions that experienced greater consolidation are associated with greater decline in overall healthcare spending. Finally, in our primary exercise, we exploit transitions of patients across organizations that are driven by changes in the organizational affiliations of their primary care physicians to study the impact of organizational size on overall spending. Our preferred specification suggests that patients switching from small to large physician organizations reduce their overall healthcare spending by 16%, and that this reduction is primarily driven by a 13% reduction in primary care visits and 0.09 (21%) fewer inpatient admissions per year.

中文翻译：

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初级保健医生的整合及其对医疗保健利用的影响

我们使用 Medicare 的管理数据来记录过去十年初级保健医生的大规模整合及其对患者医疗保健利用的影响。我们首先记录了 2008 年至 2014 年间美国各地的初级保健组织进行了整合。然后我们表明，经历了更大整合的地区与整体医疗保健支出的下降幅度更大有关。最后，在我们的主要练习中，我们利用由初级保健医生的组织隶属关系的变化驱动的患者跨组织的转变来研究组织规模对总体支出的影响。我们的首选规范表明，从小型医生组织转向大型医生组织的患者将其整体医疗保健支出减少 16%，