Comparison of characteristics that fulfill “optimal graft” criteria in European and non-European transplant recipients by stem cell source. (A) 8/8 URD (n = 340), (B) CB (n = 139), (C) haploidentical donor (n = 69), and (D) 5 to 7/8 URD (n = 44). Compared with Europeans, non-European patients were more likely to receive (A) older 8/8 URDs, (B) CB grafts that were more likely to be low-dosed and/or highly mismatched, (C) similarly aged haploidentical donors (although a higher percentage of non-Europeans had donors >40 years), and (D) older 5 to 7/8 URDs. Also, non-European 5 to 7/8 URD recipients received more HLA-mismatched grafts (compared with European mismatched URD recipients) (D). Box plots (A-B,D) present age medians (solid horizontal lines), IQR (boxes), and range (bars). Dotted lines reflect “optimal” donor age cutoffs for adult donors: 35 years for 8/8 and 5 to 7/8 URDs (A,D), and 40 years for haploidentical donors (C). P values were generated by Student t tests (A,C-D) and chi-squared tests (B).