Fig. 7

MIs across the biological age subpopulations and donor characteristics (age and sex) throughout hypothermic storage from 5 to 42 days. (a) MIs across the biological age subpopulations from 5 to 42 days. MIs across donor characteristics (age and sex) for (b) U-RBCs, (c) O-RBCs, and (d) Y-RBCs. In (a), lowercase letters from a to c on each solid line represent the significant difference across storage within each subpopulation: a (P < 0.05), b (P < 0.01), c (P < 0.001), where statistically significant difference levels (between four time points of storage with a degree of freedom of 3) were calculated using the Tukey test and each group contains RBC images from all 60 donors; lowercase letters from a to b on each dotted line represent the significant difference between subpopulations of U-, O-, and Y-RBCs at each time point of storage: ns (not significant P > 0.05), a (P < 0.05), b (P < 0.01), where statistically significant difference levels (between three groups U-, O-, and Y-RBCs with a degree of freedom of 2) were calculated using the Tukey test and each group contains RBC images from all 60 donors. In (b–d), lowercase letters on each solid line represent the significant difference across storage within each donor characteristic: ns (not significant P > 0.05), b (P < 0.01), c (P < 0.001), where statistically significant difference levels (between four time points of storage with a degree of freedom of 3) were calculated using the Tukey test and each group contains RBC images from 15 donors; lowercase letters on each dotted line represent the significant difference between TM, TF, SM, and SF at each time point of storage: ns (not significant P > 0.05), b (P < 0.01), c (P < 0.001), where statistically significant difference levels (between four donor characteristics with a degree of freedom of 3) were calculated using the Tukey test and each group contains RBC images from 15 donors.