IDEAS home Printed from https://ideas.repec.org/p/amu/wpaper/2012-07.html
   My bibliography  Save this paper

Using Difference-in-Differences to Estimate Damages in Healthcare Antitrust: A Case Study of Marshfield Clinic

Author

Listed:
  • Martha A. Starr
  • R. Forrest McCluer

Abstract

In calculating damages in healthcare antitrust cases, the difference-in-difference (DID) approach provides a potentially valuable means of controlling for lawful factors that influence prices, such as case-mix and quality of care, as distinct from price differentials due to unlawful behavior. After first comparing DID to traditional methods of estimating damages, this paper uses DID to analyze data from a well-known case against Marshfield Clinic, a large multispecialty group practice that was found to have illegally allocated markets for physician services in Central Wisconsin. Using a specification similar to what was used in the case, we find that illegal behavior accounted for about two-fifths of the Clinic's extra increase in costs per patient during the damage period. The courts, however, were not persuaded that the analysis adequately controlled for legal factors. We discuss potential pitfalls in using DID to estimate damages suggested by the case, as well as possible ways around them.

Suggested Citation

  • Martha A. Starr & R. Forrest McCluer, 2012. "Using Difference-in-Differences to Estimate Damages in Healthcare Antitrust: A Case Study of Marshfield Clinic," Working Papers 2012-07, American University, Department of Economics.
    • Handle: RePEc:amu:wpaper:2012-07
    as

    Download full text from publisher

    File URL: https://drive.google.com/open?id=1pcb_fw6GpnfDxQc5lA3fYhLFlVJ3ltx8
    File Function: First version, 2012
    Download Restriction: no
    ---><---

    Other versions of this item:

    References listed on IDEAS

    as
    1. Justine S. Hastings, 2004. "Vertical Relationships and Competition in Retail Gasoline Markets: Empirical Evidence from Contract Changes in Southern California," American Economic Review, American Economic Association, vol. 94(1), pages 317-328, March.
    2. Joshua D. Angrist & Jörn-Steffen Pischke, 2010. "The Credibility Revolution in Empirical Economics: How Better Research Design Is Taking the Con out of Econometrics," Journal of Economic Perspectives, American Economic Association, vol. 24(2), pages 3-30, Spring.
    3. Gautam Gowrisankaran, 2011. "Estimating the Impact of a Hospital Merger Using the Difference-in-Differences of Prices," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 83-89.
    4. Gaynor, Martin & Vogt, William B., 2000. "Antitrust and competition in health care markets," Handbook of Health Economics, in: A. J. Culyer & J. P. Newhouse (ed.), Handbook of Health Economics, edition 1, volume 1, chapter 27, pages 1405-1487, Elsevier.
    5. Gaynor, Martin & Town, Robert J., 2011. "Competition in Health Care Markets," Handbook of Health Economics, in: Mark V. Pauly & Thomas G. Mcguire & Pedro P. Barros (ed.), Handbook of Health Economics, volume 2, chapter 0, pages 499-637, Elsevier.
    6. Richard A. Posner, 1999. "The Law and Economics of the Economic Expert Witness," Journal of Economic Perspectives, American Economic Association, vol. 13(2), pages 91-99, Spring.
    7. Gregory Leonard & G. Steven Olley, 2011. "What Can Be Learned About the Competitive Effects of Mergers from "Natural Experiments"?," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 103-107.
    8. Leemore Dafny, 2009. "Estimation and Identification of Merger Effects: An Application to Hospital Mergers," Journal of Law and Economics, University of Chicago Press, vol. 52(3), pages 523-550, August.
    9. Michael R. Baye & Joshua D. Wright, 2011. "Is Antitrust Too Complicated for Generalist Judges? The Impact of Economic Complexity and Judicial Training on Appeals," Journal of Law and Economics, University of Chicago Press, vol. 54(1), pages 1-24.
    10. Christopher Garmon & Deborah Haas-Wilson, 2011. "The Use of Multiple Control Groups and Data Sources as Validation in Retrospective Studies of Hospital Mergers," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 41-44.
    11. Gaynor, Martin, 2006. "Is vertical integration anticompetitive?: Definitely maybe (but that's not final)," Journal of Health Economics, Elsevier, vol. 25(1), pages 175-180, January.
    12. Guido W. Imbens & Jeffrey M. Wooldridge, 2009. "Recent Developments in the Econometrics of Program Evaluation," Journal of Economic Literature, American Economic Association, vol. 47(1), pages 5-86, March.
    13. Laporte, Audrey & Windmeijer, Frank, 2005. "Estimation of panel data models with binary indicators when treatment effects are not constant over time," Economics Letters, Elsevier, vol. 88(3), pages 389-396, September.
    14. Daniel L. Rubinfeld, 2010. "Econometric Issues in Antitrust Analysis," Journal of Institutional and Theoretical Economics (JITE), Mohr Siebeck, Tübingen, vol. 166(1), pages 62-77, March.
    15. Joseph Farrell & Paul Pautler & Michael Vita, 2009. "Economics at the FTC: Retrospective Merger Analysis with a Focus on Hospitals," Review of Industrial Organization, Springer;The Industrial Organization Society, vol. 35(4), pages 369-385, December.
    16. Deborah Haas-Wilson & Christopher Garmon, 2011. "Hospital Mergers and Competitive Effects: Two Retrospective Analyses," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 17-32.
    17. Joshua D. Angrist & Jörn-Steffen Pischke, 2009. "Mostly Harmless Econometrics: An Empiricist's Companion," Economics Books, Princeton University Press, edition 1, number 8769.
    18. Cameron,A. Colin & Trivedi,Pravin K., 2005. "Microeconometrics," Cambridge Books, Cambridge University Press, number 9780521848053, September.
    19. Martha A. Starr & Forrest R. McCluer, 2014. "Prices and Quantities in Health Care Antitrust Damages," Working Papers 2014-03, American University, Department of Economics.
    20. Steven Tenn, 2011. "The Price Effects of Hospital Mergers: A Case Study of the Sutter-Summit Transaction," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 65-82.
    21. Gregory Adams & Monica Noether, 2011. "Comment on "Hospital Mergers and Competitive Effects: Two Retrospective Analyses"," International Journal of the Economics of Business, Taylor & Francis Journals, vol. 18(1), pages 33-40.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Martha A. Starr & Forrest R. McCluer, 2014. "Prices and Quantities in Health Care Antitrust Damages," Working Papers 2014-03, American University, Department of Economics.

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Gaynor, Martin & Town, Robert J., 2011. "Competition in Health Care Markets," Handbook of Health Economics, in: Mark V. Pauly & Thomas G. Mcguire & Pedro P. Barros (ed.), Handbook of Health Economics, volume 2, chapter 0, pages 499-637, Elsevier.
    2. Martin Gaynor & Kate Ho & Robert J. Town, 2015. "The Industrial Organization of Health-Care Markets," Journal of Economic Literature, American Economic Association, vol. 53(2), pages 235-284, June.
    3. Gaynor, Martin & Laudicella, Mauro & Propper, Carol, 2012. "Can governments do it better? Merger mania and hospital outcomes in the English NHS," Journal of Health Economics, Elsevier, vol. 31(3), pages 528-543.
    4. Zack Cooper & Stuart V Craig & Martin Gaynor & John Van Reenen, 2019. "The Price Ain’t Right? Hospital Prices and Health Spending on the Privately Insured," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 134(1), pages 51-107.
    5. Lin, Haizhen & McCarthy, Ian M. & Richards, Michael, 2021. "Hospital Pricing Following Integration with Physician Practices," Journal of Health Economics, Elsevier, vol. 77(C).
    6. Orley Ashenfelter & Daniel Hosken & Matthew Weinberg, 2014. "Did Robert Bork Understate the Competitive Impact of Mergers? Evidence from Consummated Mergers," Journal of Law and Economics, University of Chicago Press, vol. 57(S3), pages 67-100.
    7. Csorba, Gergely & Pápai, Zoltán, 2013. "Does one more or one less mobile opertor affect prices? A comprehensive ex-post evaluation of entries and mergers in European mobile telecommunication markets," 24th European Regional ITS Conference, Florence 2013 88503, International Telecommunications Society (ITS).
    8. Cory S. Capps & Dennis W. Carlton & Guy David, 2020. "Antitrust Treatment Of Nonprofits: Should Hospitals Receive Special Care?," Economic Inquiry, Western Economic Association International, vol. 58(3), pages 1183-1199, July.
    9. Christos Genakos & Andreas Lamprinidis & James Walker, 2023. "Evaluating merger effects," CEP Discussion Papers dp1921, Centre for Economic Performance, LSE.
    10. Joel Stiebale & Florian Szücs, 2022. "Mergers and market power: evidence from rivals' responses in European markets," RAND Journal of Economics, RAND Corporation, vol. 53(4), pages 678-702, December.
    11. Peter Backus & Thien Nguyen, 2021. "The Effect of the Sex Buyer Law on the Market for Sex, Sexual Health and Sexual Violence," Economics Discussion Paper Series 2106, Economics, The University of Manchester.
    12. Stuart V. Craig & Matthew Grennan & Ashley Swanson, 2021. "Mergers and marginal costs: New evidence on hospital buyer power," RAND Journal of Economics, RAND Corporation, vol. 52(1), pages 151-178, March.
    13. Anne‐Fleur Roos & Ramsis R. Croes & Victoria Shestalova & Marco Varkevisser & Frederik T. Schut, 2019. "Price effects of a hospital merger: Heterogeneity across health insurers, hospital products, and hospital locations," Health Economics, John Wiley & Sons, Ltd., vol. 28(9), pages 1130-1145, September.
    14. Joshua D. Angrist & Jörn-Steffen Pischke, 2010. "The Credibility Revolution in Empirical Economics: How Better Research Design Is Taking the Con out of Econometrics," Journal of Economic Perspectives, American Economic Association, vol. 24(2), pages 3-30, Spring.
    15. Boockmann Bernhard & Buch Claudia M. & Schnitzer Monika, 2014. "Evidenzbasierte Wirtschaftspolitik in Deutschland: Defizite und Potentiale," Perspektiven der Wirtschaftspolitik, De Gruyter, vol. 15(4), pages 307-323, December.
    16. Ashesh Rambachan & Neil Shephard, 2019. "Econometric analysis of potential outcomes time series: instruments, shocks, linearity and the causal response function," Papers 1903.01637, arXiv.org, revised Feb 2020.
    17. Caroline S. Carlin & Roger Feldman & Bryan Dowd, 2017. "The impact of provider consolidation on physician prices," Health Economics, John Wiley & Sons, Ltd., vol. 26(12), pages 1789-1806, December.
    18. Beard, T. Randolph & Ford, George S. & Saba, Richard P. & Seals, Richard A., 2012. "Internet use and job search," Telecommunications Policy, Elsevier, vol. 36(4), pages 260-273.
    19. Millimet, Daniel L. & Bellemare, Marc, 2023. "Fixed Effects and Causal Inference," IZA Discussion Papers 16202, Institute of Labor Economics (IZA).
    20. Nicolas R. Ziebarth, 2018. "Social Insurance and Health," Contributions to Economic Analysis, in: Health Econometrics, volume 127, pages 57-84, Emerald Group Publishing Limited.

    More about this item

    Keywords

    healthcare antitrust; differences-in-differences; damage estimation JEL Classifications: I11; L4; K21; K41; C20;
    All these keywords.

    JEL classification:

    • I - Health, Education, and Welfare

    NEP fields

    This paper has been announced in the following NEP Reports:

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:amu:wpaper:2012-07. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Thomas Meal (email available below). General contact details of provider: http://www.american.edu/cas/economics/ .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.