The liver allocation policy has been updated with a revision of the geographic preferences, as well as a more nuanced consideration of blood type compatibility. For the geographic preferences, instead of ranking patients based on local, regional, or national registration, patients are distinguished based on the distance (in nautical miles) between the transplant hospital and the donor hospital.
Under the new policy, the highest priority goes to Status 1A patients for whom the distance between hospitals is no more than 500 nm. Then patients with higher MELD scores receive priority, with an additional preference for patients within 150 nm, then 250 nm, then 500 nm, and a matching of O blood type donors with O or B blood type recipients. Status 1A patients beyond 500 nm come in after patients with a MELD score of 15 and a distance within 500 nm. The current policy is here, and the ranking system for adults is on pages 41-42.