To identify the causal relationship between health-care spending and infant health, we employ the following source of identifying variation: hospital crowdedness measured in its simplest form, by the number of infants born on a given day in a given hospital. The thought experiment is during a crowded time; infants receive less medical care because resource constraints are binding. Using detailed information on every birth in California from 2002 to 2006, we find that hospital crowdedness reduces spending for at-risk infants. Our main finding is that at-risk infants who had more intensive hospital stays because they were born on slow days fared no better than their busy day counterparts. Specifically, the mortality gains from additional spending are negligible, and additional spending increases unscheduled hospital readmission rates in the first year of life. Our findings are robust to alternative measures of crowdedness that account for hospital crowdedness on the days surrounding the birth. When we use alternative measures of treatment intensity (length of stay and delivery spending), we find similar results. Our results suggest that when forced to reduce the intensity of treatment, the health-care system does so in a way that does not harm health.

中文翻译：

---

婴儿手推车和婴儿健康：医院拥挤，医院支出和婴儿健康

为了确定医疗保健支出与婴儿健康之间的因果关系，我们采用以下识别差异的来源：医院拥挤以最简单的形式进行衡量，即根据给定医院在特定日期出生的婴儿数量来衡量。思维实验是在一个拥挤的时期。由于资源限制，婴儿获得的医疗护理较少。使用2002年至2006年加利福尼亚州每例婴儿的详细信息，我们发现医院拥挤会减少高危婴儿的支出。我们的主要发现是，由于在缓慢的一天出生而高强度住院的高危婴儿的表现并不比忙碌的同龄人好。具体来说，额外支出带来的死亡率增长微不足道，以及额外的支出会增加出生后第一年计划外的住院率。我们的发现对于替代人口拥挤度的测量方法是有力的，这些替代性措施可以解释出生后几天的医院人口拥挤度。当我们使用治疗强度（住院时间和分娩花费的时间）的替代方法时，我们会发现类似的结果。我们的结果表明，当被迫降低治疗强度时，卫生保健系统以不会损害健康的方式这样做。