Evaluating Measures of Hospital Quality: Evidence from Ambulance Referral Patterns
利用救护车公司偏好作为工具变量，检验常用医院质量指标能否预测患者再住院率和死亡率，发现高质量医院比低质量医院的效果好10%到15%。
Abstract Hospital quality measures are crucial to a key idea behind health care payment reforms: “paying for quality” instead of quantity. Nevertheless, such measures face major criticisms largely over the potential failure of risk adjustment to overcome endogeneity concerns when ranking hospitals. In this paper, we test whether patients treated at hospitals that score higher on commonly used quality measures have better health outcomes in terms of rehospitalization and mortality. To compare similar patients across hospitals in the same market, we exploit ambulance company preferences as an instrument for hospital choice. We find that a variety of measures that insurers use to measure provider quality are successful: choosing a high-quality hospital compared to a low-quality hospital results in 10% to 15% better outcomes.