May 25, 2016
Dear Mrs. Walsh and Dr. Sweet,
The liver redistricting proposal is to be offered for Public Comment in August as detailed in
the minutes of the Liver and Intestine Committee Meeting of January 21, 2016. The premise
of this proposal is that by better matching organ supply to waiting list demand, also known as
listings, more lives are assumed to be saved. The developers predict that their proposal will
result in similar allocation MELD scores across donor service areas and between the new
regions. We have serious concerns about this proposal. These include the manner in which
it was developed and the lack of consideration for the major negative consequences of
implementation. We believe that these concerns must be addressed before this proposal
goes out for Public Comment. We write to you requesting assistance in achieving this goal
and detail our concerns regarding redistricting below.
The underlying principal of redistricting is that normalizing allocation MELD scores leads to
equity or, as the developers describe it, “justice” (1). MELD as a reliable predictor of
mortality, however, applies only to the calculated laboratory MELD score and not to exception
MELD scores (2,3). The allocation MELD score is a composite of both exception scores that
vary greatly between regions and the true calculated laboratory MELD scores that do not;
these will vary greatly between regions that will combine under redistricting (figure 1). With
an over-representation of exception MELD scores in some regions, an overestimate in
mortality risk is created in these regions and it is these same regions that stand to receive an
increase in organ offers as a function of an artificial demand created through exceptions
(Arrow A, figure 1)(2, 3). A more appropriate and unutilized metric to equalize wait list
mortality is removal from the waiting list for disease progression or death. During the first
forum, the transplant community overwhelmingly voted that waiting list survival should be a
measured benefit in any new allocation policy, and maps should not be based solely on
reducing the variation in median MELD at transplant. Collectively, these simple observations
on metrics are a compelling argument against redistricting as a revision to the current
allocation and distribution system.
Multiple runs of the Liver Simulated Allocation Model (LSAM) to evaluate redistricting
demonstrated at best a minimal (2%) decrease in waiting list deaths per year in the 4 district
model nationally as compared to the existing system and even less (1%) in an 8-district
model. However, to achieve even this goal, a variety of assumptions must be met with
implementation of the policy. More importantly, the developers characterize not transplanting
an appropriately listed patient and preferential allocation to a higher MELD as a ‘life saved’,
which is not accurate. In fact, shifting organs from an appropriately listed patient with
transplant benefit (MELD >16) leaves this patient to one of two outcomes: getting sicker to
attain an offer or death while waiting. Merion established that a clear survival benefit exists
for anyone transplanted with a calculated MELD score over 16 (4). Coupling the recent policy
of Share 35 to redistricting leads to increased competition, which the developers suggest will
lessen organ discards. LSAM, however, a tool used to predict what will occur based upon our
past behaviors, predicts 200 fewer transplants with redistricting. Recent data shows
competition in fact increases discards (5, 6). However, another validated function of
increased competition is MELD inflation, which carries significant economic and outcome
consequences and has not been reported in the developers’ analyses of the impact of the
redistricting policy (7, 8, 9, 10). In summary both LSAM and literature predict a decline in the
total number of transplants with redistricting, significant MELD escalation, significant
increases in cost to OPOs, many transplant centers and to the system (8, 19, 22, 32).
The final rule 121.8 paragraph 5, specifically states that a new system must be designed to
preserve utility (11). Performing transplants in greater numbers of patients with MELD > 35
is inconsistent with the Final Rule as post-transplant mortality increases by greater than 5%
(comparing outcomes for MELD >35 to outcomes for MELD 20-25) with this policy (9, 11).
Interestingly it is the Final Rule that the developers use to justify a major change to the
existing allocation system (1, 12). So when share 35 and redistricting are coupled, the
simulated prediction of the 100 additional lives saved is exceeded by the 200 fewer
transplants done per year and the additional (approximately) 60 or potentially more posttransplant lives lost. As such, redistricting is counter to both the top priority of the OPTN
Board of Directors for 2015-2018 by resulting in fewer transplants and to the final rule
121.8 paragraph 5 on 2 points: “Shall be designed to avoid wasting organs” and to
promote the efficient management of organ placement.
A further unrecognized consequence of redistricting will be the impact on Simultaneous
Liver and Kidney (SLK) Transplant rates that have increased 20% since Share 35 (9).
Since 2001 and the introduction of MELD, SLKs have increased from 135 in 2001 to 629 in
2015. Under redistricting, LSAM, although not yet asked to model this, will predict a further
increase in SLK transplants over time. Unfortunately, a consequence of redistricting will be
increased waiting times and mortality rates on separate renal transplant wait lists. Decreasing
access to lower KDPI kidneys that are usually more often allocated with SLKs carries
additional consequences. We acknowledge that new work is being done to decrease SLKs,
but these policies have yet to be implemented or proven effective. In the end, this policy will
contribute to a larger opportunity cost borne by Medicare and those on the renal transplant
wait list. These observations lead many to seriously question the concept of redistricting and
we feel that the developers have underemphasized these impacts.
At both public fora on redistricting, the transplant community emphasized that energy should
be focused on increasing donation and improving the use of our current donor supply.
Focusing on redistricting distracts from the only action that will save more lives and increase
the number of transplants—increasing donation. Gentry et al. (13, 14) published two
manuscripts stating that redistricting would balance and not shift organs from high to low
performing OPOs. However, within their own manuscript, they acknowledge that shifts will
occur. Unfortunately, several in the scientific community question the statistical methodology
supporting their conclusion that no major shifts from high to low performing OPOs will occur.
Unfortunately, the inability to publically question their data is created by an under-recognized
editorial bias that is not uncommon within the editorial process (15). A balance of opinion
must be attained and all parties provided a voice to develop the optimal policy. It is
disappointing to also note that the SRTR has not yet assisted Professor Sanjay Mehrotra by
providing him access to LSAM as they stated they would.
Any model that compromises donation warrants great scrutiny (16, 17). The Gentry model
uses current waiting list numbers and not incidence of disease. In addition, the model
ignores access to the wait list for that population and waiting list mortality once listed. The
model will remove some of the incentive to improve donor identification and utilization in
underperforming donor service areas (DSAs) by supplementing their poor performance with
additional organs from other better performing DSAs (13,14, 25). Redistricting also penalizes
underserved areas, in particular the South, where access to transplantation waiting lists and
the potential to survive when on a wait lists is lower (Figure 2) (18). With redistricting, OPOs
will see a shift in charges for organs and some OPOs subjected to significant financial
consequence as outlined by Kappel, et. al. (19). With these additional costs to OPOs’,
resources will need to shift from efforts to increase donation to other administrative and cost
containment actions required to offset the economic impact of the redistricting policy.
Behavioral economics indicate that increasing supply to an area with high demand leads to
behaviors that maintain demand as described by Nash. Physician and institutional behaviors
have been demonstrated to align with behaviors that increase revenues (20) and this
competitive behavior illustrated to have negative consequences (21). Our concern is that
under a veil of saving more lives, centers will more aggressively list and thereby further drive
demand. This action however will likely disadvantage other areas within the same new
super-region. Another major concern with negative impact, documented in JAMA, will occur
in Veterans awaiting transplantation. The Veterans Affairs (VA) System has waitlist mortality
rates higher than the general waitlist for any given MELD score (18). Therefore, should the
MELD score in VA systems rise, which will occur for the three largest VA programs in the
country under redistricting, a disproportionate increase in wait list mortality will occur for the
VA. No data exists on exactly how redistricting will impact the VA system’s waiting list
population or finances. This is also true for center level data in regions that will do fewer
transplants following redistricting.
The community remains deeply divided on redistricting as a function of the many elements
identified during three years of data presentation, analyses, and debates. These important
issues have not been adequately analyzed or mitigated in the design of the current policy and
their potentially negative impact is an unacceptable oversight. All parties have a conflict of
interest when presenting their position on the subject as, “a conflict of interest is a set of
circumstances that creates a risk that professional judgment or actions regarding a primary
interest will be unduly influenced by a secondary interest”(24). The developers of redistricting
have consistently denied a conflict of interest but by this definition they may be the most
conflicted. In drafting this letter, we acknowledge our conflicts and confine our arguments to
seeking no greater a number of lives lost, no MELD escalation and our concerns regarding
the many economic consequences of this policy. We agree with the concept of greater
sharing to address inequity, but we do not feel redistricting solves this problem. With
redistricting we predict an increase in mortality from end stage liver disease, most noticeably
in the South. This increase in mortality will occur when donated organs are redirected from
areas with a high incidence of liver disease and limited community resources to areas with a
high incidence of wait listing and extensive community resources to support the wait listed
population. Those with greater resources live in the Northeast and benefit by greater “liver
flow” with redistricting, while those without resources are in the South (figure 2) and stand to
see a reduction in transplant numbers. This unfortunate result of the redistricting concept
creates an inequity in the chance at living.
Focusing our communal energy and resources to increasing donation and maximizing organ
utilization will save more lives by providing a greater number of transplant opportunities rather
than shuffling who gets the existing opportunity. If underperforming DSAs in regions of low
donation are given assistance, an increase in all transplants would occur (25). By reducing
discard rates and increasing utilization we will better address the inequities of geography (5,
26). However when the creators of redistricting describe "Gerrymandering for Justice" (1),
and when a trail of papers appear in the press satisfying the criteria for publication bias (15),
it becomes imperative for UNOS to investigate and assure the community that the policy and
those that develop it have been impartial and unbiased in their position.
Based on these concerns, we request that the UNOS board:
1. Instruct the liver intestine committee to abandon consideration of nationwide
redistricting proposals and consider alternative solutions to address disparities.
2. Develop a model of allocation that incorporates metrics of fairness, utility, and value,
including waiting-list mortality and long-term survival to optimize utility.
3. Allow time for recent policy revisions like share 35, sodium MELD, HCC exception
revisions and the National Review Board to be implemented and studied before
implementing further changes.
4. Perform appropriate and detailed impact analyses and vulnerability assessments on
any proposal, including but not limited to logistical difficulties, economic
consequences, effects upon smaller centers and rural communities, women, VA
patients and VA programs.
5. Arrange for LSAM assumptions, input and output data be validated by external and
impartial parties.
6. When using LSAM to predict outcomes, use data current rather than data unrelated to
existing policies.
7. Accept that parties have heuristics and biases and these can only be managed
through a balanced, more diversified and transparent process of data presentation and
publication.
8. Direct energies and refine existing policies to facilitate increasing organ supply and
reward its utilization.
In contrast to the liver transplant era before the final rule, when donation well exceeded
concerns regarding appropriate allocation, we are now in an era when demand exceeds
supply in all areas of the country (i.e. we are resource constrained). Required, then, are
policies that allocates to those with survival benefit, (i.e optimizes utility), rather than
changing to a system that reduces the total number of transplants at a higher cost. We must
explore all efforts to increase the donor pool and to this increased pool also seek policies and
practices that enhance the utilization of these precious resources. In the end, it is only
through a larger resource that we will realistically save more lives as redistricting in the end
only alters where the life waiting is lost.
Sincerely,
Alabama
Joseph Tector, MD
Professor of Surgery
Director, Xenotransplant Institute
Division of Transplantation
Department of Surgery
The University of Alabama at Birmingham School of Medicine
Birmingham, AL
Arkansas
Daniel Borja-Cacho, MD
Surgical Director, Liver Transplantation
Department of Surgery
University of Arkansas for Medical Sciences
Little Rock, AR
Colorado
Igal Kam, MD
Chief of Transplant Surgery
Professor of Surgery
Division of Transplant Surgery
University of Colorado School of Medicine
Anschutz Medical Campus
Aurora, CO
Kian A. Modanlou, MD, FACS
Surgical Director, Liver Transplant
Porter Adventist Hospital Transplant Center
Denver, CO
Florida
Ken Andreoni, MD
Interim Chair, Division of Transplantation
Department of Surgery
University of Florida Health
College of Medicine
Gainesville, FL
Georgia
Joseph F. Magliocca, MD, FACS
Surgical Director, Liver Transplantation
Associate Professor of Surgery
Department of Surgery, Division of Transplantation
Emory Transplant Center and
Children’s Healthcare of Atlanta
Atlanta, GA
Harrison S. Pollinger, D.O., FACS
Program Director, Piedmont Transplant Institute
Surgical Director of Liver Transplantation
Piedmont Healthcare
Atlanta, GA
Hawaii
Linda L. Wong, M.D.
Director, Liver Transplant Program
Queen’s Medical Center
Honolulu, HI
Illinois
Michael M. Abecassis, MD, MBA, FACS, FRCS(C), FACPE
J. Roscoe Miller Distinguished Professor
Departments of Surgery and Microbiology-Immunology
Chief, Division of Organ Transplantation
Founding Director, Comprehensive Transplant Center
Dean, Clinical Affairs
Feinberg School of Medicine
Northwestern University
Chicago, IL
Indiana
Jonathan A. Fridell, MD, FACS
Professor of Surgery
Surgical Director, Liver & Pancreas Transplantation
Chief Medical Officer, IU Health Transplant Institute
Interim Chief, Division of Transplant Surgery
Indiana University School of Medicine
Indianapolis, IN
Kellie Hanner
President/CEO
Indiana Donor Network
Indianapolis, IN
Iowa
Kenneth P. Kates, MBA
Chief Executive Officer, University of Iowa Hospitals and Clinics
Associate Vice President, University of Iowa Health Care
Iowa City, IA
Alan Reed, MD, MBA
Professor and Chief, Division of Transplant and Hepatobiliary Surgery
Director, UIHC Organ Transplant Center
University of Iowa Hospitals and Clinics
Iowa City, IA
Kansas
Timothy M. Schmitt, MD
Director, Center for Transplantation
Assistant Professor of Surgery and Internal Medicine
The University of Kansas Hospital
Kansas City, KS
Kentucky
Christopher M. Jones, MD, FACS
Associate Professor of Surgery
Director, Section of Hepatobiliary and Transplant Surgery
Chief, Liver Transplantation
University of Louisville/Jewish Hospital
Louisville, KY
Malay Shah, MD
Surgical Director, Liver Transplantation Program
Assistant Professor of Surgery
Transplant Center
University of Kentucky HealthCare
Lexington, KY
Louisiana
Joseph F. Buell, MD, MBA, FACS
Professor of Surgery and Pediatrics
Director, Abdominal Transplant Institute
Hepatobiliary Surgery and Oncology
Department of Surgery
Tulane University School of Medicine
New Orleans, LA
Pam Gillette, MPH, RN, FACHE
Vice President, Transplant
Tulane University School of Medicine
New Orleans, LA
Mary Killackey, MD, FACS
Associate Professor of Surgery and Pediatrics
Tulane University School of Medicine
New Orleans, LA
George E. Loss, Jr., MD, FACS, PhD
Associate Medical Director and System Chairman, Department of Surgery
Chief, The Ochsner Multi-Organ Transplant Institute
New Orleans, LA
Anil Paramesh, MD, FACS
Associate Professor of Surgery, Urology and Pediatrics
Tulane University School of Medicine
New Orleans, LA
Kelly Ranum
Chief Executive Officer
Louisiana Organ Procurement Agency
Metairie, LA
Gazi B. Zibari, MD, FACS
Director, John C. McDonald Regional Transplant Center
Director, WK Advanced Surgery Center
Willis-Knighton Health System
Shreveport, LA
Michigan
Marwan S. Abouljoud, MD, FACS
Benson Ford Chair
Director, Transplant Institute
Division of Transplant and Hepatobiliary Surgery
Department of Surgery
Henry Ford Hospital
Detroit, MI
Mississippi
Christopher D. Anderson, MD, FACS
James D. Hardy Professor
Chair, Department of Surgery
Chief, Division of Transplant and Hepatobiliary Surgery
The University of Mississippi Medical Center
Jackson, MS
M. Kevin Stump
President / CEO
Mississippi Organ Recovery Agency
Flowood, MS
Missouri
Diane Brockmeier
President & CEO
Mid-America Transplant
St. Louis, MO
William Chapman, MD, FACS
Eugene M. Bricker Chair of Surgery
Professor and Chief, Section of Transplantation
Chief, Division of General Surgery
Surgical Director, Transplant Center
Washington University School of Medicine
St. Louis, MO
Jameson Forster, MD, FACS
Medical Director, Abdominal Transplant
Saint Luke’s Hospital of Kansas City
Kansas City, MO
Henry B. Randall, MD, FACS
Director, Abdominal Transplant Center
Saint Louis University Hospital
St. Louis, MO
North Carolina
Lon Eskind, MD
Surgical Director, Liver Transplant
Carolinas HealthCare System
Charlotte, NC
David A. Gerber, MD, FACS
Chief and Professor of Surgery
Director, Division of Abdominal Transplantation
Department of Surgery
The University of North Carolina
Chapel Hill, NC
Lloyd Jordan
Chief Executive Officer
Carolina Donor Services
Durham, NC
Mark Russo, MD
Medical Director, Liver Transplant
Carolinas HealthCare System
Charlotte, NC
Ohio
Barry C. Massa
Executive Director
LifeCenter Organ Donor Network
Cincinnati, OH
Shimul A. Shah, MD, MHCM
Associate Professor of Surgery
Director, Liver Transplantation and Hepatobiliary Surgery
Department of Surgery
Division of Transplantation
University of Cincinnati
Cincinnati, OH
Marti Taylor, MSN, RN
Chief Executive Officer, University Hospital
Executive Director, The Richard M. Ross Heart Hospital
Wexner Medical Center
The Ohio State University
Columbus, OH
Oklahoma
Vivek Kohli, MD, FACS
Director, Liver Transplant & Hepatobiliary Pancreas Surgery
INTEGRIS Health
Nazih Zuhdi Transplant Institute
Oklahoma City, OK
Oregon
Susan L. Orloff, MD, FACS, FAASLD
Professor of Surgery
Chief and Director, Abdominal Organ Transplantation/Hepatobiliary Surgery
Adjunct Professor, Molecular Microbiology& Immunology
Oregon Health & Science University
Chief, Portland VA Medical Center Transplant Program
Portland, OR
South Carolina
Prabhakar K. Baliga, MD, FACS
Fitts-Raja Professor of Surgery
Chairman, Department of Surgery
Medical University of South Carolina
Charleston, SC
Amy Hauser
Administrator, Transplant Center
Medical University of South Carolina
Charleston, SC
Nancy A. Kay
President/CEO
LifePoint, Inc.
North Charleston, SC
Tennessee
Douglas W. Hanto, MD, PhD
Director, Vanderbilt Transplant Center
Professor of Surgery, Department of Surgery
Chief, Pediatric Liver Transplant Program
Monroe Carell Jr. Children’s Hospital at Vanderbilt
Vanderbilt University Medical Center
Nashville, TN
Texas
Jeffrey Fair, MD
Director, Transplant Programs
The University of Texas Medical Branch
Galveston, TX
Glenn Halff, MD
Professor of Surgery
Dielmann Chair in Transplant Sciences
Director, Transplant Center
University of Texas Health Science Center
San Antonio, TX
Göran B. Klintmalm, MD, PhD, FACS
Chief and Chairman
Annette C. and Harold C. Simmons Transplant Institute
W.W. Caruth Jr., Chair in Organ Transplantation Immunology
Vice Chair, Department of Surgery
Division Chief, Transplant Surgery
Professor of Surgery, Texas A&M College of Medicine
Baylor University Medical Center
Dallas, TX
Patricia Niles
President and CEO
Southwest Transplant Alliance
Dallas, TX
Teresa Shafer, RN, MSN, CPTC
President
Texas Transplantation Society, Inc.
Austin, TX
Virginia
Douglas M. Heuman, MD, FACP, FACG, AGAF, FAASLD
Professor of Medicine, Virginia Commonwealth University
Chief, Hepatology and Liver Transplantation
Hunter Holmes McGuire Department of Veterans Affairs Medical Center
Richmond, VA
Tim Jankiewicz
Vice President and Executive Director
LifeNet Health OPO
Virginia Beach, VA
Marlon Levy, MD, FACS
Professor and Chairman
Hume-Lee Transplant Center
Division of Transplantation Surgery
Virginia Commonwealth University
Richmond, VA
Shawn J. Pelletier, MD
Associate Professor of Surgery
Surgical Director, Liver Transplantation
University of Virginia Health System
Charlottesville, VA
Washington
Jorge D. Reyes, M.D.
Roger K Giesecke Distinguished Professor
Professor and Chief
Division of Transplant Surgery
Department of Surgery
University of Washington Medicine
Seattle, WA
Wisconsin
Mike Anderson
Executive Director
University of Wisconsin Organ and Tissue Donation
Madison, WI
Dixon B. Kaufman, MD, PhD
Ray D. Owen Professor and Chair
Department of Surgery
Division of Transplantation
University of Wisconsin School of Medicine and Public Health
Madison, WI
Figure 1: A Black arrows point to median laboratory MELD scores in regions that combine under a 4 district model Arrow [A] shows direction of m ovement of livers created by artificial the MELD inflation created by exceptions Figure 2: References with supporting data.
1. Gentry S, Chow E, Massie A, Segev D. Gerrymandering for Justice: Redistricting U.S.
Liver Allocation. Interfaces 2015. 45(5):462-480.
2. Berry K, Ioannou GN. Comparison of Liver Transplant-Related Survival Benefit in
Patients With Versus Without Hepatocellular Carcinoma in the United States.
Gastroenterology. 2015 Sep;149(3):669-80; quiz e15-6. doi:
10.1053/j.gastro.2015.05.025. Epub 2015 May 27.
3. Northup PG, Intagliata NM, Shah NL, Pelletier SJ, Berg CL, Argo CK. Excess mortality
on the liver transplant waiting list: unintended policy consequences and Model for EndStage Liver Disease (MELD) inflation. Hepatology. 2015 Jan;61(1):285-91. doi:
10.1002/hep.27283. Epub 2014 Oct 29.
4. Merion RM, Schaubel DE, Dykstra DM, Freeman RB, Port FK, Wolfe RA. The survival
benefit of liver transplantation. Am J Transplant. 2005;5:307–313.
5. Goldberg DS, French B, Lewis JD, Scott FI, Mamtani R, Gilroy R, Halpern SD, Abt PL.
Liver transplant center variability in accepting organ offers and its impact on patient
survival. Journal of Hepatology. 2015 Nov 25. pii: S0168-8278(15)00773-4. doi:
10.1016/j.jhep.2015.11.015. [Epub ahead of print]
6. Skaro AI, Hazen G, Ladner D, Kaplan B. Organ Transplantation: An Introduction to
Game Theory. Transplantation. 2015 Jul;99(7):1316-20.
7. Adler JT, Yeh H, Markmann JF, Nguyen LL. Market Competition and Density in Liver
Transplantation: Relationship to Volume and Outcomes. J Am Coll Surg. 2015
Aug;221(2):524-31. doi: 10.1016/j.jamcollsurg.2015.04.018. Epub 2015 May 13.
8. Salvalaggio PR, Dzebisashvili N, MacLeod KE, Lentine KL, Gheorghian A, Schnitzler
MA, Hohmann S, Segev DL, Gentry SE, Axelrod DA. The interaction among donor
characteristics, severity of liver disease, and the cost of liver transplantation. Liver
Transpl. 2011 Mar;17(3):233-42.
9. Edwards EB, Harper AM, Hirose R, Mulligan DM. The Impact of Broader Regional
Sharing of Livers: 2 Year Results of "Share 35" (LT-15-441). Liver Transpl. 2016 Feb
17 [Epub ahead of print]
10. Massie AB, Caffo B, Gentry SE, Hall EC, Axelrod DA, Lentine KL, Schnitzler MA,
Gheorghian A, Salvalaggio PR, Segev DL. MELD Exceptions and Rates of Waiting
List Outcomes. Am J Transplant. 2011 Nov;11(11):2362-71.
11. Code of Federal Regulations. Title 42, Chapter I, Subchapter K, Part 121, Section
121.8 Allocation of organs. 64 FR 56659, Oct. 20, 1999, as amended at 64 FR 71626,
Dec. 21, 1999.
12. Gentry SE, Massie AB, Cheek SW, Lentine KL, Chow EH, Wickliffe CE, Dzebashvili N,
Salvalaggio PR, Schnitzler MA, Axelrod DA, Segev DL. Addressing Geographic
Disparities in Liver Transplantation Through Redistricting. American Journal of
Transplantation. 2013 July 9. DOI: 10.1111/ajt.12301
13. Gentry SE, Chow EK, Massie A, Luo X, Shteyn E, Pyke J, Zaun D, Snyder JJ, Israni
AK, Kasiske B, Segev DL. Liver sharing and organ procurement organization
performance under redistricted allocation. Liver Transpl. 2015 Aug;21(8):1031-9. doi:
10.1002/lt.24171.
14. Gentry SE, Chow EK, Massie A, Luo X, Zaun D, Snyder JJ, Israni AK, Kasiske B,
Segev DL. Liver sharing and organ procurement organization performance. Liver
Transpl. 2015 Mar;21(3):293-9. doi: 10.1002/lt.24074.
15. Dickerson K. The existence of publication bias and risk factors for its occurrence.
JAMA. 1990 Mar 9;263(10):1385-9.
16. Mehrotra S, Kilambi V, Gilroy R, Ladner DP, Klintmalm GB, Kaplan B. Modeling the
allocation system: principles for robust design before restructuring. Transplantation.
2015 Feb;99(2):278-81.
17. Mehrotra, S. Theories in Modeling the Allocation System, Principles for Robust Design
Before Restructuring. Presentation at The Educational Public Form on Redesigning
Liver Distribution. Liver Redistricting Forum. Chicago June 22, 2015.
18. Goldberg DS, French B, Forde KA, Groeneveld PW, Bittermann T, Backus L, Halpern
SD, Kaplan DE. Association of distance from a transplant center with access to waitlist
placement, receipt of liver transplantation, and survival among US veterans. JAMA.
2014 Mar 26;311(12):1234-43.
19. Kappel DF, Chapman WC, Conrad S, Reed A, Linderer R, Dunn S, Niles P, Levy MF,
Cawiezell T. Organ Procurement Organization Liver Acquisition Costs Could More
Than Double With Proposed Redistricts. Am J Transplant. 2015 Aug;15(8):2269-70.
20. Blanco JC, Fawson C. Empiric examination of physician behavior in a changing
healthcare market. Am J Manag Care. 1997 Nov;3(11):1709-15.
21. Carreyrou J. Doing a Volume of Business. Wall Street Journal. Nov 21, 2008.
22. Schladt D, Pyke J, Gentry S, Schnitzler M, Israni AK, Kasiske BL, Lake JR, Leppke
SN, Zeglin J. Data request from the OPTN Liver and Intestinal Organ Transplantation
Committee: Supply/Demand Ratios, Proximity Points, and Additional Financial
Analyses. Meeting: February 2, 2015 (committee leadership meeting).
23. http://www.transplantequity.org/newsroom/category/in-the-news
24. Conflict of Interest in Medical Research, Education, and Practice. Institute of Medicine
(US) Committee on Conflict of Interest in Medical Research, Education, and Practice;
Lo B, Field MJ, editors. Washington (DC): National Academies Press (US); 2009.
25. Goldberg DS, French B, Abt PL, Gilroy RK. Increasing the Number of Organ
Transplants in the United States by Optimizing Donor Authorization Rates. Am J
Transplant. 2015 Aug;15(8):2117-25.
26. Gentry SE, Chow EK, Dzebisashvili N, Schnitzler MA, Lentine KL, Wickliffe CE,
Shteyn E, Pyke J, Israni A, Kasiske B, Segev DL, Axelrod DA. The Impact of
Redistricting Proposals on Health Care Expenditures for Liver Transplant Candidates
and Recipients. Am J Transplant. 2016 Feb;16(2):583-93. doi: 10.1111/ajt.13569.
Epub 2016 Jan 18.
27. Adler JT, Yeh H, Markmann JF, Axelrod DA. Is Donor Service Area Market
Competition Associated With Organ Procurement Organization Performance?
Transplantation. 2015 Oct 29. [Epub ahead of print]
28. Axelrod DA, Guidinger MK, Finlayson S, Schaubel DE, Goodman DC, Chobanian M,
Merion RM. Rates of solid-organ wait-listing, transplantation, and survival among
residents of rural and urban areas. JAMA. 2008 Jan 9;299(2):202-7. doi:
10.1001/jama.2007.50.
29. Dzebisashvili N, Massie AB, Lentine KL, Schnitzler MA, Segev D, Tuttle-Newhall J,
Gentry S, Freeman R, Axelrod DA. Following the organ supply: assessing the benefit
of inter-DSA travel in liver transplantation. Transplantation. 2013 Jan 27;95(2):361-71.
doi: 10.1097/TP.0b013e3182737cfb.
30. Moylan CA, Brady CW, Johnson JL, Smith AD, Tuttle-Newhall JE, Muir AJ. Disparities
in liver transplantation before and after introduction of the MELD score. JAMA. 2008
Nov 26;300(20):2371-8.
Loss, G. There Will Be Blood: Liver Fracking. ASTS Winter Symposium. 2016 Jan.
31. Volk ML, Reichert HA, Lok AS, Hayward RA. Variation in organ quality between liver
transplant centers. Am J Transplant. 2011 May;11(5):958-64.
32. D. A. DuBay, P. A. MacLennan, R. D. Reed, M. Fouad, M. Martin, C. B. Meeks, G.
Taylor, M. L. Kilgore, M. Tankersley, S. H. Gray, J. A. White, D. E. Eckhoff, J. E. Locke
The Impact of Proposed Changes in Liver Allocation Policy on Cold Ischemia Times
and Organ Transportation Costs. Volume 15, Issue 2, pages 541–546, February 2015.