The evolution of kidney exchange--the operational side of market design

 Market design doesn't stop when the market opens, and it isn't all analytical--a lot of it is operational, with changes being called for as experience is accumulated. One of the big problems faced by all of the multi-hospital kidney exchange networks is that many proposed transplants don't go through.  For example, if a three way cycle is proposed and one of the proposed transplants isn't accepted, none of the three proposed transplants go through. Counted this way, initially only 15% of proposed transplants were realized, but changes in the way surgeons' preferences are elicited has now brought this nearer to 50%. ( It turns out it's not easy to elicit surgeons' preferences in advance, but we're making progress:)

Here's an account of some of the ongoing market design in kidney exchange, at the Alliance for Paired Donation.  The American Journal of Transportation has now made it open access, after naming it among the 10 "best of AJT 2015" articles.

Fumo, D.E., V. Kapoor, L.J. Reece, S.M. Stepkowski,J.E. Kopke, S.E. Rees, C. Smith, A.E. Roth, A.B. Leichtman, M.A. Rees, “Improving matching strategies in kidney paired donation: the 7-year evolution of a web based virtual matching system,” American Journal of Transplantation, forthcoming, Article first published online: 26 MAY 2015 | DOI: 10.1111/ajt.13337, http://onlinelibrary.wiley.com/doi/10.1111/ajt.13337/epdf

Abstract: Failure to convert computer-identified possible kidney paired donation (KPD) exchanges into transplants has prohibited KPD from reaching its full potential. This study analyzes the progress of exchanges in moving from ‘‘offers’’ to completed transplants. Offers were divided into individual segments called 1-way transplants in order to calculate success rates. From 2007 to 2014, the Alliance for Paired Donation performed 243 transplants, 31 in collaboration with other KPD registries and 194 independently. Sixty-one of 194 independent transplants (31.4%) occurred via cycles, while the remaining 133 (68.6%) resulted from nonsimultaneous extended altruistic donor (NEAD) chains. Thirteen of 35 (37.1%) NEAD chains with at least three NEAD segments accounted for 68% of chain transplants (8.6 tx/chain). The ‘‘offer’’ and 1-way success rates were 21.9 and 15.5%, respectively. Three reasons for failure were found that could be prospectively prevented by changes in protocol or software: positive laboratory crossmatch (28%), transplant center declined donor (17%) and pair transplanted outside APD (14%). Performing a root cause analysis on failures in moving from offer to transplant has allowed the APD to improve protocols and software. These changes have improved the success rate and the number of transplants performed per year.
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Here are the other "10 best" articles .
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It turns out that several of my papers in the past year were about kidneys, with a focus on operational issues:

      Anderson, Ross, Itai Ashlagi, David Gamarnik and Alvin E. Roth, “Finding long chains in kidney exchange using the traveling salesmen problem,” Proceedings of the National Academy of Sciences of the United States of America (PNAS), January 20, 2015 | vol. 112 | no. 3 | 663–668, http://www.pnas.org/content/112/3/663.full.pdf+html 

      Anderson, Ross, Itai Ashlagi, David Gamarnik, Michael Rees, Alvin E. Roth, Tayfun Sönmez and M. Utku Ünver, " Kidney Exchange and the Alliance for Paired Donation: Operations Research Changes the Way Kidneys are Transplanted," Edelman Award Competition, Interfaces, 2015, 45(1), pp. 26–42. http://pubsonline.informs.org/doi/pdf/10.1287/inte.2014.0766

     

Roth, Alvin E., “Transplantation: One Economist’s Perspective,” Transplantation, February 2015,  Volume 99 - Issue 2 - p 261–264. http://marketdesigner.blogspot.com/2015/02/an-economists-perspective-on.html

    

Fumo, D.E., V. Kapoor, L.J. Reece, S.M. Stepkowski,J.E. Kopke, S.E. Rees, C. Smith, A.E. Roth, A.B. Leichtman, M.A. Rees, “Improving matching strategies in kidney paired donation: the 7-year evolution of a web based virtual matching system,” American Journal of Transplantation, October 2015, 15(10), 2646-2654 http://onlinelibrary.wiley.com/enhanced/doi/10.1111/ajt.13337/ (designated one of 10 “best of AJT 2015”)