is measured in months. For status 3 (or 4) patients, who have the least urgent need for transplantation, waiting times may reach years. Historically, more than 50 percent of the patients awaiting liver transplants at any given time have been classified as status 3 (see Table 5-1 and Appendix B, Tables B-1, B-4, B-6, and B-9).

In issuing the Final Rule, the Department of Health and Human Services (1998b) used regional differences in median waiting times for all patients combined as a basis for claiming that inequities exist in the allocation of organs to transplant patients. Panel 1 of Figure 5-1 illustrates the differences in median waiting times among the 11 UNOS regions, grouped by quartiles, for all liver transplant candidates registered between January 20, 1998, and January 19, 1999. Although dividing the waiting time distribution into quartiles oversimplifies these data, this method is similar to that used in previous analyses by DHHS. On this basis, median waiting times are shortest in the South and upper Midwest and longest in New England and the Northwest (including Alaska). However, given that the majority of transplant patients are classified as status 3, these differences principally reflect the differences in waiting time of status 3 patients (see panel 5), who have the least serious need and, therefore, the longest wait for transplantation. Panels 2 and 3 show that statuses 1 and 2A patients contribute little or no regional variability in overall waiting times. Panels 4 and 5 show that variability in overall waiting time is produced almost entirely by statuses 2B and 3 patients.