Online Appendix and Estimation Code
We document four similarities between American human healthcare and American pet care: (i) rapid growth in spending as a share of GDP over the last two decades; (ii) strong income-spending gradient; (iii) rapid growth in the employment of healthcare providers; and (iv) similar propensity for high spending at the end of life. We speculate about possible implications of these similar patterns in two sectors that share many common features but differ markedly in institutional features, such as the prevalence of insurance and of public sector involvement.
Impacts of performance pay for hospitals: The Readmissions Reduction Program
Job Market Paper
Policy makers are increasingly tying payments for health care providers to their performance on quality measures, though there is little empirical evidence to guide the design of such incentives. I deploy administrative Medicare claims data to study
a large federal program which penalizes hospitals with high rates of repeat hospitalizations (''readmissions''). I exploit the introduction of the penalty and policy-driven variation in penalty across hospitals to identify the effect of the program on hospital admission and treatment decisions, and on patient health. The program is associated with a 5% decrease in readmission accompanied by a 3% reduction in thirty day mortality. I quantify the role of two mechanisms - improvement in treatment quality and changes in admitting behavior - and find that quality improvement can explain 55-60% of the aggregate decrease. The change in admitting behavior seems driven by the penalty since there is a substantial decrease in admission rate for returning patients that could potentially incur a penalty but no such effect for those that will not. It plays a quantitatively important role and I find suggestive evidence of harm to affected patients.
Do Medicaid HMOs reduce utilization? Evidence from Florida obstetrics
An early version was awarded "Best Second Year Paper" by the Department of Economics
Using hospital discharge data on Medicaid patients, I test whether physicians choose C-sections less often for HMO patients relative to non-HMO patients. I find that the odds of an HMO patient receiving a primary C-section are about 40% lower, holding all else equal. The effect is heterogeneous and declines in magnitude as patients become more complex. A stylized principal-agent model of physician procedure choice estimates that physicians put about 20% less weight on patient related factors for non-HMO patients relative to HMO enrollees. Hence the agency distortion is more severe in the case of non-HMO patients.
Work in Progress
Estimating effects of public insurance expansion for adults: Evidence from California hospitals (Draft coming soon)
with Mark Duggan and Emilie Jackson
The Affordable Care Act authorized the largest expansion of public insurance coverage in decades, at substantial cost to US taxpayers. While there is consensus that the law led to a substantial decline in un-insurance, effects on utilization of care and health are not well understood. We use the universe of discharge data from hospitals and Emergency rooms in California over 2008-15 to examine crowd-out of other types of existing insurance and short-term effects on health care utilization and patient health. Our identification strategy exploits fuzzy discontinuities in public insurance coverage at specific ages where individuals were historically forced out, but subsequently allowed under the ACA. We find evidence of substantial crowd-out of county insurance programs (young) and private insurance (old) -- implying this was a large transfer from federal taxpayers to local governments and individuals. There is compelling evidence that patients choose privately owned over public hospitals once they receive coverage -- but only suggestive evidence of improvement in health outcomes such as mortality or avoidable care. Financial benefits for hospitals are more readily apparent. Hospitals previously serving a high share of un-insured patients benefit disproportionately with a 10% increase in total revenue relative to remaining hospitals.
Chasing ambulance productivity (Slides)
with Nicholas Bloom and David Chan
Using ambulance dispatch, clinical outcome, billing, and personnel data on millions of ambulance runs in a large ambulance chain, we evaluate variation in productivity across ambulance sites and personnel. The data include detailed information on time spent at the scene of emergency, travel times, and travel distance. We find significant differences in productivity within sites across workers, and that these differences are highly correlated across roles in ambulance teams. We further investigate the role of tenure in productivity and find evidence that suggests a non-monotonic pattern in productivity over tenure, with productivity first increasing then decreasing. Finally, we evaluate changes in manager identities and individual managerial interventions to study the impact of managerial decisions on site productivity.