In kidney exchange programmes patients with end-stage renal failure may exchange their willing, but incompatible living donors among each other. National kidney exchange programmes are in operation in ten European countries, and some of them have already conducted international exchanges through regulated collaborations. The exchanges are selected by conducting regular matching runs (typically every three months) according to well-defined constraints and optimisation criteria, which may differ across countries. In this work we give integer programming formulations for solving international kidney exchange problems, where the optimisation goals and constraints may be different in the participating countries and various feasibility criteria may apply for the international cycles and chains. We also conduct simulations showing the long-run effects of international collaborations for different pools and under various national restrictions and objectives. We compute the expected gains of the cooperation between two countries with different pool sizes and different restrictions on the cycle-length. For instance, if country A allows 3-way cycles and country B allows 2-way cycles only, whilst the pool size of country A is four times larger than the pool size of country B (which is a realistic case for the relation of Spain and France, respectively), then the increase in the number of transplants will be about 2% for country A and about 37% for country B.
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In this study we focus on the collaboration of countries and a key aspect of this collaboration is the assumption that they all follow commonly agreed protocols. As such, there is no need to incentivise countries to register their patient-donor pairs, unlike for the American hospitals. We will however compare the consecutive and the joint pool scenarios in our simulations, as these are both used in practice. We will not consider compensations, or any strategic issues, but we will allow the countries to have different constraints and goals with regard to the cycles and chains they may be involved in. In particular, we will compare the benefits of the countries from international collaborations when they have different upper bounds on their national cycles, and thus also possible different constraints on the segments of the international cycles they are participating in. As an example we mention the Austro-Czech cooperation, where Austria requires to have all exchanges simultaneously, so they allow short national cycles and short segments only, whilst in Czech Republic longer non-simultaneous cycles and chains are also allowed. We formulate novel IP models for dealing with potentially diverse constraints and goals in international kidney exchange programmes and we test two-country cooperation scenarios under different assumptions over their constraints, the possibility of having chains triggered by altruistic donors, and the sizes of their pools.
As an example, we describe the full IP-model for a problem setting that is representing the cooperation between Austria and Czech Republic. Here Austria allows only short national cycles and short segments, whilst Czech Republic allows unbounded national cycles and unbounded segments in international cycles, and we require that every international cycle has only one segment in each country. This IP formulation was implemented and used in the simulations for the two-country cases, that we described in Sect. 4.
We conduct long-term simulations with agents arriving and leaving the pool such as in Santos et al. (2017), (e.g. with 3-months matching runs for 3 years). We restrict our attention to maximising the size of the solutions, and do not consider scoring methods or any other objective. We conduct the simulations for the two-country case, as the effects of the cooperation for a country can already be tested on this simple setting. The instances were generated by the web app developed by James Trimble ( -webapp/#/generator) using the Saidman generator parameter setting available in that application.
To determine the benefits of international KEPs we conduct a case study involving two countries which aim to develop a joint KEP and are concerned about the advantages and disadvantages of cooperation between their KEPs. We compare the individual benefits from the no cooperation case to the consecutive matching and merged pool scenarios. We illustrate the differences between no cooperation and merged pools cases with a small example in Fig. 1.
The simulation involves 20 instances each containing the compatibility information for 1000 patient-donor pairs. For the sake of simplicity, although our model can handle altruist donors (who start chains), for the case study we only consider the cyclic exchanges among incompatible patient-donor pairs. The reason for this choice is to be able to more clearly see the difference in cooperation (because adding chains may dramatically increase the number of transplants in any given KEP stage). The length of the considered time-frame for the simulated kidney exchange scenarios is 3 years with matching runs scheduled every 3 months for each instance. Every agent is assigned an uniformly distributed arrival time to the KEP and the patient-donor pairs stay in the KEP for a maximum of 1 year (or 4 matching runs) after which they leave the programme (which means that they opt for an alternative solution, such as having a direct ABO-incompatible transplant after desensitisation or getting a deceased organ).
To understand the importance of the parameters of collaboration presented in Sect. 4 we conduct a sensitivity analysis by considering most of the combinations possible. We illustrate the impact of both programme pool size and local policy constraints on the cooperation of KEPs by:
Then, in the second row of Fig. 2 we demonstrate the effects of local KEP constraints on the matched pairs by only changing the local constraint in country 2 (now has local cycle bound 2 and international cooperation can be done with 2-cycles and 3-cycles with only one participant patient-donor pair in country 2). Note that the patient compatibility and arrival time to the programme was not modified.
In every scenario the objective is simply to maximise the number of transplants. There are three settings for collaboration: no cooperation (i.e. separate KEPs, baseline scenario), consecutive matchings (each country runs a local KEP optimisation and then the remaining patient pools enter a joint KEP) and full collaboration (a single KEP for both countries).
This article is based upon work from COST Action ENCKEP: European Network for Collaboration on Kidney Exchange Programmes (CA15210), supported by COST (European Cooperation in Science and Technology); see www.cost.eu.
After extensive formative research on childhood pneumonia in Uttar Pradesh and Bihar (14 districts), we found that pneumonia related morbidity and mortality can be averted if the following barriers are addressed: (a) delay in symptom recognition (b) delay in timely and qualified health care seeking (c) distrust of the community on the available public health services [3]. Thereafter, we developed and validated text, audio, video messages to address these barriers [4]. Specifically, messages were developed on (a) symptom recognition (b) where and when to seek treatment (c) how to approach a care provider and negotiate for quality of care (d) risk vulnerability perception. The proposed project aims to leverage the extensive work done and conduct operations research to address these three barriers to health care seeking through innovative community based approaches using messages developed by us as well as by strengthening the existing public health system.
The project staff will document the PAS proceedings, noting the number of persons who attended a particular session. The queries asked by attendees will be noted and over time a question and answer book will be prepared. On-site visits and telephonic contact will be made to validate conduction of PAS sessions. The project staff will conduct exit interviews of about 10% of the attendees noting their understanding of the materials explained to them and their satisfaction, using a pre-developed open-ended questionnaire (qualitative research methodology).
Technical Advisory Group (TAG) for the project will be constituted to ensure quality control and government buy-in for the research findings. Members from government and non-government sectors, civil society organizations, grass root workers, academia and sponsors will be part of TAG. This group will meet twice, first at the time of project initiation and then immediately before project completion. 2ff7e9595c
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