The organ center of the United Network for Organ Sharing and twenty years of organ sharing in the United States.

The increasing size of the transplant waiting list and the increasing use of expanded criteria donors places a premium on efficient use of recovered organs. Maximal organ utilization often necessitates organ sharing between transplant organizations. Optimal organ sharing requires rapid, integrated communication of donor information combined with expedited organ transportation. For more than 20 years, the United Network for Organ Sharing's Organ Center has fulfilled this task for the United States transplant community. This overview details a brief history of United States organ sharing and the role played by the Organ Center. The current scope and modes of Organ Center operations are detailed.

Transplant data: sources, collection, and caveats.

By examining the sources, quality and organization of transplant data available, as well as making observations about data reporting patterns and accuracy, we hope to improve understanding of existing results, help researchers with study design and stimulate new exploratory initiatives. The primary data source, collected by the OPTN, has benefited from extensive recent technological advances. Transplant professionals now report patient and donor data more easily, quickly, and accurately, improving data timeliness and precision. Secondary sources may be incorporated, improving the accuracy and expanding the scope of analyses. For example, auxiliary mortality data allows more accurate survival analysis and conclusions regarding the completeness of center-reported post-transplant follow-up. Furthermore, such sources enable examination of outcomes not reported by centers, such as mortality after waiting list removal, providing more appropriate comparisons of waiting list and post-transplant mortality. Complex collection and reporting processes require specific analytical methods and may lead to potential pitfalls. Patterns in the timing of reporting adverse events differ from those for 'positive' events, yielding the need for care in choosing cohorts and censor dates to avoid bias. These choices are further complicated by the use of multiple sources of data, with different time lags and reporting patterns.