Predictive value of HLA-A, -B, -C, and -DR low-resolution typing for subsequent matching after high-resolution typing. The frequency of unrecognized high-resolution mismatches in pairs selected using low-resolution typing for HLA-A, -B, and -DR ± HLA-C. “6of6” match refers to pairs matched at low resolution for HLA-A, -B, and -DR (n = 1422). “5 of 6” match refers to pairs with a single low-resolution mismatch for HLA-A, -B, or -DR (n = 429). “8 of 8” match refers to pairs matched at low resolution for HLA-A, -B, -C, and -DR (n = 1047). The data show the frequency of pairs with 0, 1, 2, 3, and 4 or more allele-level mismatches in each cohort.