NBER Publications by John A. Graves

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February 2017Evaluating Measures of Hospital Quality
with Joseph J. Doyle, Jr., Jonathan Gruber: w23166
In response to unsustainable growth in health care spending, there is enormous interest in reforming the payment system to ā€œpay for quality instead of quantity.ā€ While quality measures are crucial to such reforms, they face major criticisms largely over the potential failure of risk adjustment to overcome endogeneity concerns. In this paper we implement a methodology for estimating the causal relationship between hospital quality measures and patient outcomes. To compare similar patients across hospitals in the same market, we xploit ambulance company preferences as an instrument for patient assignment. We find that a variety of measures used by insurers to measure provider quality are successful: assignment to a higher-scoring hospital results in better patient outcomes. We estimate th...
March 2015Uncovering Waste in U.S. Healthcare
with Joseph Doyle, Jonathan Gruber: w21050
There is widespread agreement that the US healthcare system wastes as much as 5% of GDP, yet little consensus on what care is actually unproductive. This partly arises because of the endogeneity of patient choice of treatment location. This paper uses the effective random assignment of patients to ambulance companies to generate comparisons across similar patients treated at different hospitals. We find that assignment to hospitals whose patients receive large amounts of care over the three months following a health emergency do not have meaningfully better survival outcomes compared to hospitals whose patients receive less. Outcomes are related to different types of treatment intensity, however: patients assigned to hospitals with high levels of inpatient spending are more likely to survi...
March 2012Do High-Cost Hospitals Deliver Better Care? Evidence from Ambulance Referral Patterns
with Joseph J. Doyle, Jr., Jonathan Gruber, Samuel Kleiner: w17936
Endogenous patient sorting across hospitals can confound performance comparisons. This paper provides a new lens to compare hospital performance for emergency patients: plausibly exogenous variation in ambulance-company assignment. Ambulances are effectively randomly assigned to patients in the same area based on rotational dispatch mechanisms. Using Medicare data from 2002-2008, we show that ambulance company assignment importantly affects hospital choice for patients in the same zip code. Using data for New York state from 2000-2006 that matches exact patient addresses to hospital discharge records, we show that patients who live very near each other but on either side of ambulance-dispatch boundaries go to different types of hospitals. Both strategies show that higher-cost hospitals hav...

Published: "Measuring Returns to Hospital Care: Evidence from Ambulance Referral Patterns." (with John Graves, Jonathan Gruber, and Samuel Kleiner) Journal of Political Economy, Volume 123, Number 1, February 2015

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