Allan B. Massie

Concerns have been raised that optimized redistricting of liver allocation areas might have the unintended result of shifting livers from better‐performing to poorer‐performing organ procurement organizations (OPOs). We used liver simulated allocation modeling to simulate a 5‐year period of liver sharing within either 4 or 8 optimized districts. We investigated whether each OPO's net liver import under redistricting would be correlated with 2 OPO performance metrics (observed to expected liver yield and liver donor conversion ratio), along with 2 other potential correlates (eligible deaths and incident listings above a Model for End‐Stage Liver Disease score of 15). We found no evidence that livers would flow from better‐performing OPOs to poorer‐performing OPOs in either redistricting scenario. Instead, under these optimized redistricting plans, our simulations suggest that livers would flow from OPOs with more‐than‐expected eligible deaths toward those with fewer‐than‐expected eligible deaths and that livers would flow from OPOs with fewer‐than‐expected incident listings to those with more‐than‐expected incident listings; the latter is a pattern that is already established in the current allocation system. Redistricting liver distribution to reduce geographic inequity is expected to align liver allocation across the country with the distribution of supply and demand rather than transferring livers from better‐performing OPOs to poorer‐performing OPOs. Liver Transpl 21:1031‐1039, 2015. © 2015 AASLD.

Recent allocation policy changes have increased the sharing of deceased donor livers across local boundaries, and sharing even broader than this has been proposed as a remedy for persistent geographic disparities in liver transplantation. It is possible that broader sharing may increase cold ischemia times (CITs) and thus harm recipients. We constructed a detailed model of transport modes (car, helicopter, and fixed-wing aircraft) and transport times between all hospitals, and we investigated the relationship between the transport time and the CIT for deceased donor liver transplants. The median estimated transport time was 2.0 hours for regionally shared livers and 1.0 hour for locally allocated livers. The model-predicted transport mode was flying for 90% of regionally shared livers but for only 22% of locally allocated livers. The median CIT was 7.0 hours for regionally shared livers and 6.0 hours for locally allocated livers. Variation in the transport time accounted for only 14.7% of the variation in the CIT, and the transport time on average composed only 21% of the CIT. In conclusion, nontransport factors play a substantially larger role in the CIT than the transport time. Broader sharing will have only a marginal impact on the CIT but will significantly increase the fraction of transplants that are transported by flying rather than driving. Liver Transpl 20:1237-1243, 2014. © 2014 AASLD.

We present the design, methods and population characteristics of a large community trial that assessed the efficacy of a weekly supplement containing vitamin A or beta-carotene, at recommended dietary levels, in reducing maternal mortality from early gestation through 12 weeks postpartum. We identify challenges faced and report solutions in implementing an intervention trial under low-resource, rural conditions, including the importance of population choice in promoting generalizability, maintaining rigorous data quality control to reduce inter- and intra- worker variation, and optimizing efficiencies in information and resources flow from and to the field.