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Is Drug Coverage a Free Lunch? Cross-Price Elasticities and the Design of Prescription Drug Benefits


  • Martin Gaynor
  • Jian Li
  • William B. Vogt


Recently, many U.S. employers have adopted less generous prescription drug benefits. In addition, the U.S. began to offer prescription drug insurance to approximately 42 million Medicare beneficiaries in 2006. We use data on individual health insurance claims and benefit data from 1997-2003 to study the effects of changing consumers' co-payments for prescription drugs on the quantity demanded and expenditure on prescription drugs, inpatient care and outpatient care. We allow for effects both in the year of the co-payment change and in the year following the change. Our results show that increases in prescription drug prices reduce both the use of and spending on prescription drugs. However, consumers substitute the use of outpatient care and inpatient care for prescription drug use, and about 35% of the expenditure reductions on prescription drugs are offset by the increases in other spending.

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  • Martin Gaynor & Jian Li & William B. Vogt, 2006. "Is Drug Coverage a Free Lunch? Cross-Price Elasticities and the Design of Prescription Drug Benefits," NBER Working Papers 12758, National Bureau of Economic Research, Inc.
  • Handle: RePEc:nbr:nberwo:12758
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    References listed on IDEAS

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    Cited by:

    1. Marianne Simonsen & Lars Skipper & Niels Skipper, 2016. "Price Sensitivity of Demand for Prescription Drugs: Exploiting a Regression Kink Design," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 31(2), pages 320-337, March.
    2. Tomas J. Philipson & Dana Goldman, 2007. "Integrated Insurance Design in the Presence of Multiple Medical Technologies," American Economic Review, American Economic Association, vol. 97(2), pages 427-432, May.
    3. Alan M. Garber & Jonathan Skinner, 2008. "Is American Health Care Uniquely Inefficient?," Journal of Economic Perspectives, American Economic Association, vol. 22(4), pages 27-50, Fall.
    4. Shi, Lijia & Gao, Zhifeng & Chen, Xuqi, 2014. "The cross-price effect on willingness-to-pay estimates in open-ended contingent valuation," Food Policy, Elsevier, vol. 46(C), pages 13-21.

    More about this item

    JEL classification:

    • D12 - Microeconomics - - Household Behavior - - - Consumer Economics: Empirical Analysis
    • I10 - Health, Education, and Welfare - - Health - - - General
    • M50 - Business Administration and Business Economics; Marketing; Accounting; Personnel Economics - - Personnel Economics - - - General

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