Shedding new light onto the ceiling and floor? A quantile regression approach to compare EQ-5D and SF-6D responses
AbstractAn important issue in the measurement of health status concerns the extent to which an instrument displays lack of sensitivity to changes in health status at the extremes of the distribution, known as floor and ceiling effects. Previous studies use relatively simple methods that focus on the mean of the distribution to examine these effects. The aim of this paper is to determine whether quantile regression using longitudinal data improves our understanding of the relationship between quality of life instruments. The study uses EQ-5D and SF-36 (converted to SF-6D values) instruments with both baseline and follow-up data. Relative to ordinary least least-squares (OLS), a first difference model shows much lower association between the measures, suggesting that OLS methods may lead to biased estimates of the association, due to unobservable patient characteristics. The novel finding, revealed by quantile regression, is that the strength of association between the instruments is different across different parts of the health distribution, and is dependent on whether health improves or deteriorates. The results suggest that choosing one instrument at the expense of another is difficult without good prior information surrounding the expected magnitude and direction of health improvement related to a health-care intervention. Copyright © 2009 John Wiley & Sons, Ltd.
Download InfoIf you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
Bibliographic InfoArticle provided by John Wiley & Sons, Ltd. in its journal Health Economics.
Volume (Year): 19 (2010)
Issue (Month): 6 ()
Contact details of provider:
Web page: http://www3.interscience.wiley.com/cgi-bin/jhome/5749
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Koenker,Roger, 2005.
Cambridge University Press, number 9780521845731, November.
- Eric W. Christensen, 2004. "Scale and scope economies in nursing homes: A quantile regression approach," Health Economics, John Wiley & Sons, Ltd., vol. 13(4), pages 363-377.
- John Brazier & Mark Deverill, 1999. "A checklist for judging preference-based measures of health related quality of life: Learning from psychometrics," Health Economics, John Wiley & Sons, Ltd., vol. 8(1), pages 41-51.
- John Brazier & Jennifer Roberts & Aki Tsuchiya & Jan Busschbach, 2004. "A comparison of the EQ-5D and SF-6D across seven patient groups," Health Economics, John Wiley & Sons, Ltd., vol. 13(9), pages 873-884.
- Brazier, John & Roberts, Jennifer & Deverill, Mark, 2002. "The estimation of a preference-based measure of health from the SF-36," Journal of Health Economics, Elsevier, vol. 21(2), pages 271-292, March.
- Winkelmann, Rainer, 2006. "Reforming health care: Evidence from quantile regressions for counts," Journal of Health Economics, Elsevier, vol. 25(1), pages 131-145, January.
- Bernie J. O'Brien & Marian Spath & Gordon Blackhouse & J.L. Severens & Paul Dorian & John Brazier, 2003. "A view from the bridge: agreement between the SF-6D utility algorithm and the Health Utilities Index," Health Economics, John Wiley & Sons, Ltd., vol. 12(11), pages 975-981.
- Louise Longworth & Stirling Bryan, 2003. "An empirical comparison of EQ-5D and SF-6D in liver transplant patients," Health Economics, John Wiley & Sons, Ltd., vol. 12(12), pages 1061-1067.
- Gunasekara, Fiona Imlach & Carter, Kristie & Blakely, Tony, 2012. "Comparing self-rated health and self-assessed change in health in a longitudinal survey: Which is more valid?," Social Science & Medicine, Elsevier, vol. 74(7), pages 1117-1124.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Wiley-Blackwell Digital Licensing) or (Christopher F. Baum).
If references are entirely missing, you can add them using this form.