Skip to main content

Ethical Considerations of Continuous Distribution in Organ Allocation

eye iconAt a glance

Current policy

The Organ Procurement and Transplantation Network (OPTN) is working to develop a system of allocating deceased donor organs called Continuous Distribution. This new approach will consider many factors that contribute to a successful transplant. In this new approach, patients will be ranked with an overall score that is determined by considering multiple patient factors, which are called “attributes”.

The purpose the OPTN Ethics Committee’s White Paper is to serve as a reference tool for organ specific committees to use as they develop ethically sound policies using the Continuous Distribution framework.

Supporting media


View presentation PDF link


  • Reference tool for organ specific committees to utilize as they move forward developing an ethically sound continuous distribution framework
  • Highlights possible areas of discussion and aims to assist organ specific committees in closing potential gaps in equity, utility, transparency and autonomy
  • Aims to contribute to the development of the best possible continuous distribution system
  • Furthers discussions within the community of what makes up an ethical organ allocation framework
  • This document should be viewed broadly and considered during the development of each organ system’s allocation framework

Anticipated impact

  • What it's expected to do
    • The paper is expected to discuss and expand upon ethical principles that organ specific OPTN committee members should consider when making changes to their respective organ’s policy and allocation process
  • What it won't do
    • The paper will not provide required criteria for how organ specific OPTN committees are supposed to change policy and allocation


  • Ethical considerations
  • Utility
  • Equity
  • Transparency and autonomy

Terms to know

  • Ethical Principle of Utility: The greatest benefit for the entire community.
  • Ethical Principle of Equity: The fair pattern of distribution of benefits.
  • Ethical Principle of Transparency and autonomy: Association with the ethical principle of respect for persons, and holds that actions or practices tend to be right insofar as they respect individual’s independent choices, as long as the choices do not impose harm on others, and the ability to easily understand any new allocation rules and processes.
  • Continuous Distribution: The name of the new approach the OPTN uses to develop a more equitable system of allocating organs.
  • Composite Allocation Score: The number used in Continuous Distribution that will be assigned to waiting list patients. This score is determined by using several patient factors.

Click here to search the OPTN glossary

eye iconComments

Patient Affairs Committee | 10/01/2021

The Patient Affairs Committee (PAC) appreciates the work of the Ethics Committee in developing this proposal and for the opportunity to comment on it. The PAC review group agreed with the vast majority of the content in the white paper and had additional questions about the maintenance, revision, and oversight of this new type of allocation framework. Members had mixed feelings about how easily understood continuous distribution would be to patients – some concerned about patients understanding the framework while others felt it was more patient oriented than the existing system. Members felt comfortable with the work of the organ specific committees in developing this framework coupled with these ethical considerations. The PAC specifically appreciates the sections on equity, transparency, and patient autonomy, as these are areas of great concern to the patient population. Overall, the PAC is supportive of the Ethics Committee’s white paper and is appreciative of the opportunity to provide the unique patient perspective.

Transplant Families | 09/30/2021

Transplant Families appreciates the opportunity to offer the recipient parents and their family's perspective. We support the white paper with the following caveats. We must address children being listed at or around the age of transitioning to adulthood. This group is already at a disadvantage and shows graft loss for a variety of reasons. Let's give them a fighting chance and if they are listed under 18, let them keep that pediatric priority. We would like to echo SPLIT in saying that all children are a vulnerable population, that we need to pay special attention to metrics in this group, and that this can therefore improve community awareness and hopefully be the beginning of real change for mitigating unnecessary loss or missed opportunities in this age group.

Anonymous | 09/30/2021

Region 11 sentiment: 6 strongly support, 9 support, 4 neutral/abstain, 0 oppose, 0 strongly oppose Comments: This was not discussed during the meeting but OPTN representatives were able to submit comments with their sentiment, and two attendees commented that additional evaluation should be done on the distribution of marginal organs to consider distance traveled and increases in CIT and discards, adding that there needs to be a more timely and efficient way to allocate to the centers that will actually accept these marginal kidneys earlier in the allocation process to hopefully transplant. One attendee noted that the categories and weights are essential and the decisions in regards to this really need involvement from representatives from all types of centers. Another attendee commented that there needs to be transparency as we introduce changes in organ distribution, adding that too often there is concern that the modeling is done without input from frontline teams. Finally, an attendee supported the work being done to continue to refine the continuous fair distribution in organ allocation for all organs.

Anonymous | 09/30/2021

The Pediatric Committee thanks the OPTN Ethics Committee for the opportunity to review their white paper. The Committee provides the following feedback: The Committee emphasized the importance of calling out the pediatric population in Ethics Committee white papers as a vulnerable population, especially since there continues to be discussion regarding the cut off age for the pediatric definition. In this country, there is an obligation to protect minors and these discussions erode this protection. A member noted that an ethical consideration for the pediatric definition in continuous distribution should be age at disease onset instead of the age at listing for transplant, which would eliminate some of these hard boundaries. A member suggested that age could be assigned value in a continuous, but declining fashion, based on the potential benefit from an organ transplant. A member noted that, in order to do this, it would need to be discussed whether the one-year, limited, post-transplant survival outcomes are appropriate to determine utility. The Committee suggested citing the Ethics Committee’s previous white paper on the Ethical Principles of Pediatric Prioritization to show that both of these white papers are related.

Anonymous | 09/30/2021

The Minority Affairs Committee appreciates the opportunity to provide feedback on Ethical Considerations of Continuous Distribution in Organ Allocation from the Ethics Committee and provides the following comments: A member recommended that the sponsoring committee should monitor the amount of organs imported to and exported from various locations across the country vis-à-vis the rates of organ donation in affected regions. Another member agreed and suggested that OPTN Committees should be provided with monitoring reports on the Continuous Distribution model. Another member asked the sponsoring committee to consider that some minority groups may not be as involved or aware of the shift to continuous distribution and that this could disadvantage those patients.

Society for Transplant Social Workers | 09/30/2021

The Society for Transplant Social Workers shares our appreciation of the work of the Ethics committee to bring focus to the importance of equity and transparency in organ distribution. As these policies increasingly have real world exposure, we strongly encourage OPTN to be hyper aware of the impact any distribution policy change will have on at-risk and underserved patient populations.

Anonymous | 09/30/2021

Thank you for your careful evaluation of the ethical principles involved in the distribution of organs. I strongly support this white paper. Pairing the best organ with the best recipient has become increasingly complex as medical knowledge has expanded over the last few decades. Taking all of the different factors into account will hopefully lead to better access and better outcomes for patients. The white paper also appropriately recognizes the needs of vulnerable populations, such as pediatric patients. Ongoing evaluation of the impacts of continuous distribution on patients and revision of the organ specific criteria will be necessary to continue to ensure ongoing transparency, utility, and equity.

NATCO | 09/29/2021

NATCO commends the Ethics Committee in their efforts to ensure equity and transparency with the new continuous distribution allocation system. NATCO supports development of a reference tool for Committees as they develop organ specific allocation policies for the updated continuous distribution system. Having a document that serves as guidance only as opposed to in policy would prove to be helpful as OPTN Committees develop the organ specific allocation framework.

Anonymous | 09/29/2021

The Kidney Transplantation Committee appreciates the opportunity to comment on the Ethical Considerations of Continuous Distribution in Organ Allocation white paper. Committee members expressed support for these considerations. One member pointed out the ethical challenges of allocating priority to pediatric patients on a binary under or over 18 years old basis. Another member expressed support for these ethical considerations in context with community input in weighting attributes and goals. The member emphasized ethical principles will be foundationally important when developing the Continuous Distribution framework.

Anonymous | 09/29/2021

The OPTN Lung Transplantation Committee thanks the OPTN Ethics Committee for their work on this white paper and noted that the lung proposal considered these ethical considerations.

Society for Pediatric Liver Transplantation | 09/29/2021

SPLIT supports this white paper – we agree with Continuous Distribution as a strategy for improving the transparency, equity, and utility in transplant. We strongly agree that incorporating more diverse community voices – including patients/families, other stakeholders, and the general public. Ensuring consideration of values from and priorities of these stakeholders, in addition to technical transplant expertise, will be critical for new allocation systems. We urge the Committee to specifically recognize pediatric transplant candidates as a minority and vulnerable population that requires ongoing careful attention to access and is at-risk for impaired access to transplant – particularly the youngest children (under age 2) and adolescents near the transition from the “pediatric” to “adult” age group. As the Committee notes, community stakeholders overall consistently recognized pediatric priority as a top priority for lung allocation. We agree that an ideal allocation system should consider utility and equity – and that special attention to this for pediatric candidates is critical – as is recognized both in the Final Rule and on a previous Ethics Committee white paper on pediatric priority for organ allocation ( We strongly encourage the Ethics Committee to specifically reference and discuss this white paper in the Continuous Distribution white paper as an important source that Continuous Distribution ethical decisions should be consistent with. We also strongly agree with the Committee’s recognition that young adulthood (17-25 years of age) is a particularly high-risk time for graft loss and death in transplant recipients, and careful attention to post-implementation data collection for high-risk, vulnerable populations like this are critical for truly understanding the impact of Continuous Distribution or other allocation changes. We urge the Committee to plan for ongoing reviews (eg 6 months, 1 year, and annually) with a transparent reporting of the efficacy of the continuous distribution strategy to: 1.) Ensure that there has not been a disadvantage to pediatric candidates or other rare, vulnerable and/or minority groups, and 2.) To improve community awareness and confidence in this system.

Transplant Coordinators Committee | 09/29/2021

The Transplant Coordinators Committee (TCC) appreciates the work of the Ethics Committee in developing this document and for the opportunity to comment on it. The Committee feels that this guidance is well intentioned. The white paper has value in promoting equity and transparency but does not provide clear-cut ways to accomplish those goals. It is also important to balance equity with the financial impacts and having the resources necessary to manage changes. Overall, the TCC is supportive of the white paper and is appreciative of the opportunity to provide the transplant coordinator perspective.

American Society of Transplant Surgeons | 09/29/2021

The American Society of Transplantation (ASTS) supports the OPTN white paper on ethical considerations of transitioning to a Continuous Distribution organ allocation system, using lung allocation as an example. In the section on the assessment of continuous distribution on equity (pp. 17-18), the paper states that “removal of distinct geographic boundaries supports equity,” and goes on to justify this statement. This paper must acknowledge that continuous distribution will only remove distinct geographic boundaries from the allocation system but not from organ distribution, as OPOs will continue to operate within their respective donor service areas (DSA). We believe that to truly remove boundaries, the system must remove the impact of hard borders on cost. Export surcharges and import fees exacted upon transplant programs for organs that cross DSA boundaries create a financial disparity between patients located within a DSA border versus those who are outside of the DSA border. There is an ethical obligation of the transplant community to remove the financial disparities associated with moving organs across DSA boundaries in order to address the ethical principle of equity in organ allocation using a continuous distribution system. One area in which this white paper falls short is the focus on individual and population basedpatient related outcomes as practically the only metrics to consider in the assessment and implementation of a continuous distribution system. We acknowledge that the paper mentions cold time and shipping charges as additional considerations, but we recommend that additional analysis of efficiency is necessary for monitoring the effects of continues distribution. While the ASTS agrees that patient outcomes are a primary consideration, other system-level variables need to be considered. Costs, resource utilization and workload all need to be considered in how the change in allocation is affecting the organ transplant system in the United States. For example, if continuous distribution significantly increases the amount of time it takes for organ allocation, thereby increasing the workload on organ procurement organization and hospitals, this will put stress on hospitals, especially those with limited bed capacity, and require additional OPO staff, both of which will also drive up costs.

View attachment from American Society of Transplant Surgeons

Association of Organ Procurement Organizations | 09/29/2021

AOPO supports the Ethics Committee’s work in the Ethical Considerations in Continuous Distribution and recognizes the value of this document as a tool to assist the OPTN Board and Committees in developing and evaluating factors in continuous distribution (CD) framework in a manner that ensures alignment with the ethical principles of organ allocation. AOPO agrees that CD as a points-based framework has the potential to better facilitate the balancing of ethical principles at both the patient and systemwide level as compared to the prior classification system with hard boundaries. AOPO understands the use of the Lung Committee’s work as illustrative of how the delineation of factors and weighting can be accomplished under CD consistent with ethical considerations. However, AOPO suggests that some of the sections be revised to be less descriptive of the Lung Committee’s work and rather use examples from the Lung Committee to support the discussion of how CD frameworks should be developed consistent with ethical principles of allocation. See in particular the following sections: “Changes in the value weights associated with the measurements”, “Addition of New Measures” and “Using Desired Outcomes” which read like a description of what the Lung Committee has done rather than leading with what the concepts/principles are that should be considered and then describing how the Lung Committee approached that work. For example, the addition of new measures section could describe the type of factors that should be considered (height weight, living donor status, etc.) and why (ethical principles that apply like access/equity linked to height) and then describe what the lung Committee did to incorporate those factors into the CD framework. This would improve the paper as a tool in the future as other organ systems transition to CD and as a white paper reference that is more than a contemporary description of current work underway. AOPO also suggest that the section on Normative Justification be moved to the beginning of the paper as it lays out the ethical requirements for an allocation system and the alignment the CD framework provides. This sets the context for the details to follow such as weights, additional measures and identifying desired outcomes. AOPO appreciates the acknowledgement of the OPO’s role in identifying “the most economical and intelligent decision-making tools when solving the many, and often distinctive, distribution and matching problems which a complex allocation system in a big population of stakeholders precipitates” and agrees that this is an important component to operationalizing the CD allocation framework to deliver on the ethical principles its designed to achieve. To that end, AOPO would suggest that the document emphasize a responsibility for all members of the system to work together to realize the ethical benefits of the CD framework. The “rules and tools” (so to speak) that transplant programs and OPOs must follow become critical to the ethical analysis because without them, the system will not be able to deliver for patients the benefits that can be achieved through a CD framework. Finally, AOPO agrees with the point in the section on equity that donation serves all those in need not just those who are close by. We would however suggest that this section misconceives the current environment in reference to a “circle of concern” to the extent that’s a reference to DSA or 250nm. AOPO believes that the greatest wish and priority for deceased donors and their families is that their gift of life will positively impact someone that they do not know but know are in need. There are no boundaries on this priority. Finally, AOPO appreciates the attention to the anticipated challenges and the need for transitioning to CD in a manner that minimizes disruption to patients, programs and OPOs and in particular, attention to pragmatic concerns, many of which will fall on OPOs to resolve once CD is implemented. The issue of clinician behavior is one which has already been identified with the 250nm allocation frameworks and OPTN projects to address this (such as mandatory filters, clarification of provisional yes and other tools) are in process, but AOPO would urge the Ethics Committee to reference this work as critical to being able to maximize the ethical benefits that CD could provide (per point made in paragraph above). It is unclear in this section of the document what is being referenced as “outside threats to communication and technological systems” (line 1136) and AOPO would generally suggest revisions to this section as it makes references to terms like “imports” that are not defined in the document and may be confusing to broader readership. This section also seems to conflate expense and logistics which are related but not always directly correlated (for example there is a reference to the cost of shipping however this may or may not be increased through CD on either a systemwide or OPO-specific basis). AOPO would be pleased to offer some edits to this section.

American Society of Transplantation | 09/29/2021

The American Society of Transplantation is supportive of this proposal in concept. Society members reviewed the concepts contained within the public comment document, including all potential ethical principles and?the?potential impact of a continuous distribution in?U.S.?organ transplant allocation. Overall, there was general consensus that the principles outlined in the document were well presented and?supported?by the OPTN. There was also appreciation for the depth?in?which the OPTN delved into the ethical principles of continuous distribution, and that the ideas presented were of sound logic. The following comments are offered for consideration as the proposal continues to be developed. Flexibility and Adaptability Of note, a concern was raised regarding the flexibility and adaptability of a continuous distribution system within the current OPTN?review structure. Specifically, if there were changes that needed to be made (e.g. weighting of certain factors), it was not clear the process through which these changes would be made. Would the OPTN require such changes to be routed through the biannual public comment cycle, or would there be another mechanism through which the transplant community could provide feedback on proposed changes? The Workgroup requests that the OPTN clarify this process of changing a continuous distribution allocation system moving forward in order to allow for appropriate community input. Unintended Consequences for Patient Populations Concerns were raised regarding potential issues of justice and equity affecting vulnerable groups (racial and ethnic minorities or children who are a minority in transplant) are not sufficiently considered in the white paper in its current form. We propose that existing literature describing the impact of various healthcare AI systems on equity indicators should be reviewed and cited in the white paper.

ASHI | 09/28/2021

The American Society for Histocompatibility (ASHI) and its National Clinical Affairs Committee (NCAC) appreciate the opportunity to comment on the OPTN Ethics Committee’s White Paper regarding the ethical principles of incorporating the continuous distribution model in the overall organ allocation framework. ASHI is supportive of the White Paper in ensuring equity in transplant access across all patient populations, particularly those who are biologically disadvantaged as a result of their HLA diversity, sensitization status, CPRA and blood type, etc. while balancing the utility of the available organs and improving transplant outcomes.

Region 10 | 09/28/2021

Region 10 sentiment: 3 Strongly Support; 13 Support; 2 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose Comments: This was not discussed during the meeting but OPTN representatives were able to submit comments with their sentiment. The region supported the white paper, and one member noted the importance of considering Utility, if wide distribution increases costs dramatically to the system and decreases organ function. Another member stated that ethical considerations are very important, but the optimized ethical considerations may not be able to be effectively implemented given the other, real-world constraints - allocation limitations, costs, logistics - these are all becoming prohibitively burdensome as the community move to broader sharing. It was also noted that the committee should ensure that all aspects of Diversity, Equity, and Inclusion are included in future Continuous Distribution discussions. There was a suggestion that the composition of the committee should include representation from each of the different organ committees to make sure that the individual needs are met. Finally, another member echoed concerns brought forth by the Patient Affairs Committee in regards to the quantity of inputs as well as specific application to future allocation algorithms.

Region 1 | 09/24/2021

Region 1 sentiment: 1 Strongly Support, 7 Support, 0 Neutral/Abstain, 0 Oppose, 0 Strongly Oppose. No comments.

Anonymous | 09/24/2021

The Pancreas Committee thanks the OPTN Ethics Committee for the opportunity to review their public comment proposal. The Committee provides the following feedback: Members expressed appreciation for the work the Ethics Committee has done in tandem with the Kidney and Pancreas Committees as they work on the Continuous Distribution project. A member noted that the weighting of the attributes is where they see most of the value based judgements coming into play. By not just relying on the modeling and instead gathering feedback on the communities values of different attributes through the analytical hierarchy process (AHP) exercise, this creates an allocation system that more easily identifies areas where certain groups may be disadvantaged and is more responsive.

American Nephrology Nurses Association (ANNA | 09/23/2021

ANNA supports

View attachment from American Nephrology Nurses Association (ANNA

Region 6 | 09/23/2021

Region 6 sentiment: 2 Strongly Support; 8 Support; 0 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose. Comments: One attendee noted a potential recipient being listed one day before their 18th birthday versus a patient listed on their 18th birthday would dramatically change their scores. Another commenter recommended the committee assess the overall impact of continuous distribution on kidney discard rates. A third attendee expressed appreciation for the attention given to pediatric considerations in the ethics of continuous distribution in organ allocation, and noted special attention should continue to be given to pediatrics across all organs in the development of continuous distribution.

Region 8 | 09/22/2021

Region 8 sentiment: 5 strongly support, 14 support, 3 neutral/abstain, 0 oppose, 0 strongly oppose. Comments: Region 8 supports this proposal. A member provided support for the paper, and stated that overall he thinks the paper is well written and informative. But he did question whether the OPTN will review the current lung allocation proposal in the light of the included recommendations prior to making a final decision on its adoption and implementation. A member questioned whether continuous distribution is truly an ethical issue. He stated that as long as disparities remain in supply/demand, as well as other issues such as health care insurance, race, etc. there will be issues of allocation. Further, there will always be an unresolvable ethical debate of trying to balance different aspects.

Anonymous | 09/15/2021

Region 7 sentiment: 3 strongly support, 11 support, 3 neutral/abstain, 0 oppose, 0 strongly oppose. Comments: One attendee commented that protection for pediatric candidates should be underscored.

Region 9 | 09/14/2021

Region 9 sentiment:? 1 Strongly Support; 6 Support; 1 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose. No comments?.

Region 3 | 09/10/2021

Region 3 sentiment: 3 strongly support, 5 support, 6 neutral/abstain, 0 oppose, 1 strongly oppose. Region 3 supported this proposal. One attendee expressed appreciation for the work of the ethics committee.

Region 2 | 09/10/2021

• Region 2 sentiment: 7 Strongly Support, 16 Support, 2 Neutral/Abstain, 0 Oppose, 0 Strongly Oppose • Comments: This was not discussed during the meeting but OPTN representatives were able to submit comments with their sentiment. Members of the region supported the white paper, and one member stated that there needs to be consideration regarding significant increases in costs and staffing as these will further challenge organizations coupled with imminent changes to reimbursement. Another member noted that while evaluating the various attributes, it would be helpful to also consider other items that may impact the Continuous Distribution allocation system, such as the ability to handle an increased volume of organ offers. Due to the increased volume many OPOs are moving away from facilitating import offers for their local transplant centers. There are also financial implications to consider like increased transportation costs. As the community moves to a Continuous Distribution allocation system, will it decrease organ discards? Lastly, a member noted that it would be more equitable to reconsider the pediatric designation across all organ types to a youth designation and that for certain very young adults the allocation should gradually move down a scale as they age into more mature adulthood, perhaps with the scale ending at 25 years old

Anonymous | 08/30/2021

Region 5 sentiment: 7 strongly support, 16 support, 2 neutral/abstain, 1 oppose, 0 strongly oppose. Region 5 supported the white paper for Ethical Considerations of Continuous Distribution in Organ Allocation. A member stated that this is an important consideration during the transition to continuous distribution. Another member commented the regional impact of continuous distribution must occur and that there should be consideration of ethics in continuous distribution decisions.

Anonymous | 08/27/2021

1 strongly support, 9 support, 1 neutral/abstain, 0 oppose, 0 strongly oppose. Region 4 supported this whitepaper.