IDEAS home Printed from https://ideas.repec.org/a/eee/econom/v144y2008i2p341-351.html
   My bibliography  Save this article

Patient enrollment in medical trials: Selection bias in a randomized experiment

Author

Listed:
  • Malani, Anup

Abstract

Self-selection can bias estimates of treatment effects from randomized experiments if one is interested in extrapolating results to the general population. This paper notes that there is an isomorphism between the Roy model for the sorting of workers into sectors and the decision of subjects to participate in randomized experiments. The main implication is that, as the probability of receiving active treatment rises, patients who are less optimistic about new treatment will begin to enroll and estimates of treatment effects will fall. This, in turn, implies that selection bias is positive. These findings are confirmed with data from trials of ulcer medications.

Suggested Citation

  • Malani, Anup, 2008. "Patient enrollment in medical trials: Selection bias in a randomized experiment," Journal of Econometrics, Elsevier, vol. 144(2), pages 341-351, June.
  • Handle: RePEc:eee:econom:v:144:y:2008:i:2:p:341-351
    as

    Download full text from publisher

    File URL: http://www.sciencedirect.com/science/article/pii/S0304-4076(08)00032-8
    Download Restriction: Full text for ScienceDirect subscribers only
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    References listed on IDEAS

    as
    1. James J. Heckman & Jeffrey A. Smith, 1995. "Assessing the Case for Social Experiments," Journal of Economic Perspectives, American Economic Association, vol. 9(2), pages 85-110, Spring.
    2. Tomas Philipson, 1999. "External Treatment Effects and Program Implementation Bias," Working Papers 9929, Harris School of Public Policy Studies, University of Chicago.
    3. Heckman, James J & Honore, Bo E, 1990. "The Empirical Content of the Roy Model," Econometrica, Econometric Society, vol. 58(5), pages 1121-1149, September.
    4. Hadar, Josef & Russell, William R, 1969. "Rules for Ordering Uncertain Prospects," American Economic Review, American Economic Association, vol. 59(1), pages 25-34, March.
    5. Heckman, James J, 1996. "Randomization as an Instrumental Variable: Notes," The Review of Economics and Statistics, MIT Press, vol. 78(2), pages 336-341, May.
    6. A. D. Roy, 1951. "Some Thoughts On The Distribution Of Earnings," Oxford Economic Papers, Oxford University Press, vol. 3(2), pages 135-146.
    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. Sylvain Chassang & Gerard Padro I Miquel & Erik Snowberg, 2012. "Selective Trials: A Principal-Agent Approach to Randomized Controlled Experiments," American Economic Review, American Economic Association, vol. 102(4), pages 1279-1309, June.
    2. Belot, Michèle & James, Jonathan, 2014. "A new perspective on the issue of selection bias in randomized controlled field experiments," Economics Letters, Elsevier, vol. 124(3), pages 326-328.
    3. Basu, Anirban, 2015. "Welfare implications of learning through solicitation versus diversification in health care," Journal of Health Economics, Elsevier, vol. 42(C), pages 165-173.
    4. Anup Malani & Tomas J. Philipson, 2011. "Can Medical Progress be Sustained? Implications of the Link Between Development and Output Markets," NBER Working Papers 17011, National Bureau of Economic Research, Inc.
    5. Belot, Michèle & James, Jonathan, 2016. "Partner selection into policy relevant field experiments," Journal of Economic Behavior & Organization, Elsevier, vol. 123(C), pages 31-56.
    6. Jose M. Fernandez, 2013. "An Empirical Model Of Learning Under Ambiguity: The Case Of Clinical Trials," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 54(2), pages 549-573, May.
    7. Utteeyo Dasgupta & Lata Gangadharan & Pushkar Maitra & Subha Mani & Samyukta Subramanian, 2012. "Choosing to be Trained: Evidence from a Field Experiment," Monash Economics Working Papers 43-12, Monash University, Department of Economics.
    8. Chemla, Gilles & Hennessy, Christopher A., 2019. "Controls, belief updating, and bias in medical RCTs," Journal of Economic Theory, Elsevier, vol. 184(C).

    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. Heckman, James J. & Lalonde, Robert J. & Smith, Jeffrey A., 1999. "The economics and econometrics of active labor market programs," Handbook of Labor Economics, in: O. Ashenfelter & D. Card (ed.), Handbook of Labor Economics, edition 1, volume 3, chapter 31, pages 1865-2097, Elsevier.
    2. W. Bentley MacLeod, 2017. "Viewpoint: The human capital approach to inference," Canadian Journal of Economics, Canadian Economics Association, vol. 50(1), pages 5-39, February.
    3. Heckman, James, 2001. "Accounting for Heterogeneity, Diversity and General Equilibrium in Evaluating Social Programmes," Economic Journal, Royal Economic Society, vol. 111(475), pages 654-699, November.
    4. Arild Aakvik & James J. Heckman & Edward J. Vytlacil, 2000. "Treatment Effects for Discrete Outcomes when Responses to Treatment Vary Among Observationally Identical Persons: An Application to Norwegian ..," NBER Technical Working Papers 0262, National Bureau of Economic Research, Inc.
    5. Aakvik, Arild & Heckman, James J. & Vytlacil, Edward J., 2005. "Estimating treatment effects for discrete outcomes when responses to treatment vary: an application to Norwegian vocational rehabilitation programs," Journal of Econometrics, Elsevier, vol. 125(1-2), pages 15-51.
    6. James J. Heckman, 2010. "Building Bridges between Structural and Program Evaluation Approaches to Evaluating Policy," Journal of Economic Literature, American Economic Association, vol. 48(2), pages 356-398, June.
    7. Djebbari, Habiba & Smith, Jeffrey, 2008. "Heterogeneous impacts in PROGRESA," Journal of Econometrics, Elsevier, vol. 145(1-2), pages 64-80, July.
    8. Philipp Eisenhauer & James J. Heckman & Edward Vytlacil, 2015. "The Generalized Roy Model and the Cost-Benefit Analysis of Social Programs," Journal of Political Economy, University of Chicago Press, vol. 123(2), pages 413-443.
    9. James J. Heckman, 2005. "Micro Data, Heterogeneity and the Evaluation of Public Policy Part 2," The American Economist, Sage Publications, vol. 49(1), pages 16-44, March.
    10. Deborah A. Cobb‐Clark & Thomas Crossley, 2003. "Econometrics for Evaluations: An Introduction to Recent Developments," The Economic Record, The Economic Society of Australia, vol. 79(247), pages 491-511, December.
    11. Pamela Giustinelli & Matthew D. Shapiro, 2018. "SeaTE: Subjective ex ante Treatment Effect of Health on Retirement," Working Papers wp382, University of Michigan, Michigan Retirement Research Center.
    12. Burt S. Barnow & Jeffrey Smith, 2015. "Employment and Training Programs," NBER Chapters, in: Economics of Means-Tested Transfer Programs in the United States, Volume 2, pages 127-234, National Bureau of Economic Research, Inc.
    13. Paul Ellickson & Sanjog Misra, 2012. "Enriching interactions: Incorporating outcome data into static discrete games," Quantitative Marketing and Economics (QME), Springer, vol. 10(1), pages 1-26, March.
    14. D’Haultfœuille, Xavier & Maurel, Arnaud, 2013. "Inference on an extended Roy model, with an application to schooling decisions in France," Journal of Econometrics, Elsevier, vol. 174(2), pages 95-106.
    15. Pradhan, Menno & van Soest, Arthur, 1995. "Formal and informal sector employment in urban areas of Bolivia," Labour Economics, Elsevier, vol. 2(3), pages 275-297, September.
    16. Burgess, Simon & Lane, Julia & Stevens, David, 1997. "Jobs, Workers and Changes in Earnings Dispersion," CEPR Discussion Papers 1714, C.E.P.R. Discussion Papers.
    17. McLaughlin, Kenneth J & Bils, Mark, 2001. "Interindustry Mobility and the Cyclical Upgrading of Labor," Journal of Labor Economics, University of Chicago Press, vol. 19(1), pages 94-135, January.
    18. Girsberger, Esther Mirjam & Méango, Romuald & Rapoport, Hillel, 2020. "Regional migration and wage inequality in the West African economic and monetary union," Journal of Comparative Economics, Elsevier, vol. 48(2), pages 385-404.
    19. Peter Kuhn & Marie-Claire Villeval, 2011. "Do Women Prefer a Co-operative Work Environment?," Working Papers 1127, Groupe d'Analyse et de Théorie Economique Lyon St-Étienne (GATE Lyon St-Étienne), Université de Lyon.
    20. Christopher Taber & Rune Vejlin, 2020. "Estimation of a Roy/Search/Compensating Differential Model of the Labor Market," Econometrica, Econometric Society, vol. 88(3), pages 1031-1069, May.

    More about this item

    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:eee:econom:v:144:y:2008:i:2:p:341-351. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: . General contact details of provider: http://www.elsevier.com/locate/jeconom .

    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: Nithya Sathishkumar (email available below). General contact details of provider: http://www.elsevier.com/locate/jeconom .

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

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.