TABLE 1.

Categorization of Residents Versus Non-US Citizens/Non-US Residents

Study Categories	UNOS Categories
Residents	US citizens Resident aliens Non-US citizens/US residents
Presumed unauthorized immigrants*	Nonresident aliens Non-US citizens/non-US residents who traveled to the United States for reasons other than LT

^*In subsampling validation, which involved careful chart review of 41 presumed unauthorized immigrants identified at 2 centers in this study, using the corresponding UNOS categories, this algorithm had a 93% positive predictive value for identifying unauthorized immigration status at time of LT (i.e., 38 of 41 were unauthorized immigrants from foreign countries living in the United States).