Enzyme-linked immunosorbent assay (ELISA) and flow cytometric techniques have been introduced to overcome the limited sensitivity and specificity of the CDC assay. This retrospective study used lambda antigen tray-mixed screening and Luminex HLA class I and II specificity assays to re-examine: (1) the accuracy with which detection of HLA antibody and specificity by ELISA predicts pretransplantation National Institutes of Health (NIH)/Centers for Disease Control and Prevention (CDC) crossmatch; and (2) a comparison of Luminex and ELISA methods to detect HLA antibodies. Sera from 481 patients awaiting kidney transplantation were tested using the ELISA method lambda antigen tray-mixed and using NIH-CDC to determine how well HLA antibodies detected using ELISA predicted crossmatches using CDC. Pretransplantation sera from 48 patients with follow-up data were retested using both ELISA lambda antigen tray-mixed and Luminex to compare the efficacy of the 2 methods.