William Encinosa

Center for Delivery, Organization and Markets
Agency for Healthcare Research and Quality
540 Gaither Rd.
Rockville, MD 20850

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org

NBER Working Papers and Publications

November 2016Do Good Reports Mean Higher Prices? The Impact of Hospital Compare Ratings on Cardiac Pricing
with Avi Dor, Kathleen Carey: w22858
Previous research found that the initiation of Hospital Compare (HC) quality reporting had little impact on patient outcomes. However little is known about its impact on hospital prices, which may be significant since insurers are positioned to respond to quality information when engaging hospitals in price negotiations. To explore this issue we estimate variants of difference-in-difference models allowing HC impacts to vary by levels of quality scores. We separately examine the effects of the three main scores (heart attack, heart failure, and combined mortalities) on transaction prices of two related cardiac procedures: bypass surgery and angioplasty. States which had mandated reporting systems preceding HC form the control group. Analyzing claims data of privately insured patients, w...
January 2010Does Prescription Drug Adherence Reduce Hospitalizations and Costs?
with Didem Bernard, Avi Dor: w15691
We estimate the impact of diabetic drug adherence on hospitalizations, ER visits, and hospital costs, using insurance claims from MarketScan® employer data. However, it is often difficult to measure the impact of drug adherence on hospitalizations since both adherence and hospitalizations may be correlated with unobservable patient severity. We control for such unobservables using propensity score methods and instrumental variables for adherence such as drug coinsurance levels and direct-to- consumer-advertising. We find a significant bias due to unobservable severity in that patients with more severe health are more apt to comply with medications. Thus, the relationship between adherence and hospitalization will be underestimated if one does not control for unobservable severity. Overall,...

Published: Does prescription drug adherence reduce hospitalizations and costs? The case of diabetes. Encinosa, W., Bernard, D., Dor, A. "Does prescription drug adherence reduce hospitalizations and costs? The case of diabetes." Advances in Health Economics and Health Services Research, Vol. 22 151-173. Emerald Group Publishing Limited, Apr 2010.

September 2004How Does Cost-Sharing Affect Drug Purchases? Insurance Regimes in the Private Market for Prescription Drugs
with Avi Dor: w10738
Insurance for prescription drugs is characterized by two types of cost-sharing: flat copayments and variable coinsurance. We develop a theoretical model to show that refill purchases of preventive drugs (compliance) are lower under coinsurance due to the consumer's exposure to variation in drug prices. Coinsurance creates countervailing incentives. Consumers who never comply under flat copayments might find it optimal to comply if they drew a relatively low price under coinsurance. In contrast, consumers who always comply under flat copayments might stop complying if they drew a relatively high price under coinsurance. Our theory shows the second effect dominates under certain distributional assumptions about health states. Empirically, we derive comparable models for compliance behavior i...
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