Fig. 4.

Generalizability of SMI to blood samples from a third facility. (A) Additional data for comparison of SMI (as developed in this report) and conventional hemolysis scores of 20 red cell units sampled at five storage durations were analyzed at Canadian Blood Services in Edmonton, Alberta. (B) Hemolytic scores based on the standard physiological hemolysis tests for the collected red cell units. Sample 6 showed an elevated level of hemolysis from day 3 to day 42 (deeper red shades in the table, blue diamonds in B–D), which is likely due to donor factors (Materials and Methods). This data point is therefore marked as blue in the data plots but excluded from statistics. (C) SMI scores by weakly supervised learning of the corresponding red cell units. (D) The correlation between hemolysis and SMI scoring systems. Coefficient of determination R² = 0.5833. Shaded bands around the regression line display the 95% confidence interval for the regression estimate. With the inclusion of elevated hemolyzed sample (sample 6, shown as blue diamonds), the coefficient of determination R² is 0.2520, likely because the current neural network was not trained to tolerate certain confounding factors such as donor factors that lead to unusually high hemolysis levels.