Improving Broader Sharing to Address Geographic Inequity in Liver Transplantation

Abstract

Problem definition: This paper studies the deceased-donor liver allocation policies in the United States. In the transplant community, broader organ sharing is believed to mitigate geographic inequity (intergeographic variation in transplant rates, patient survival rates, waiting times, and offers) in organ access, and recent policies are moving in that direction in principle. The liver-allocation policy has gone through two major modifications in the last 10 years. Despite these overhauls, geographic inequity persists. Methodology/results: In this study, we develop a patient’s dynamic choice model to analyze the patient’s strategic response to a policy change. We use this to evaluate several (existing and proposed) organ-allocation policies. On historical data, we show that our model’s predictions are more precise than the existing liver simulated allocation model. It more accurately captures (1) a patient’s change in organ offer acceptance probability (with their sickness level) and (2) the behavioral change of a patient in terms of organ offer acceptance probability with a change in policy. Next, we study the current acuity circles policy (a one-size-fits-all variant of broader sharing) and conclude that it results in lower efficiency (more offer refusals and a lower transplant benefit) than the previous share 35 policy and performs similarly on geographic equity measures. Finally, we show that broader sharing in its current form may not be the best strategy to balance geographic equity and efficiency. The intuition is that, by indiscriminately enlarging the pool of supply locations from where patients can receive offers, they tend to become more selective, resulting in more offer rejections and less efficiency. We illustrate that a policy that equalizes the supply (deceased donors)-to-demand (waiting list patients) ratios across geographies is better than acuity circles in achieving geographic equity at the lowest trade-off on efficiency metrics. Managerial implications: The key message to policymakers is that they should move away from the one-size-fits-all approach and focus on matching supply and demand to develop organ-allocation policies that score well in terms of efficiency and geographic equity.