Multiway variable importance plot of IgA and IgG responses at 3 months after infusion (mean decrease accuracy and mean decrease Gini). This figure illustrates the importance of individual Abs in differentiating between responders and nonresponders, as assessed using the random forest model. The x-axis represents the mean decrease in accuracy, and the y-axis represents the mean decrease in Gini. Higher values on both axes indicate greater importance in the model. Abs in the upper right of the plot are identified as important by both metrics, indicating more substantial contributions to model performance. Notably, Abs that were nominally significant at the 3-month time point (P < .05) in the logistic regression models are also among the most important variables identified by the random forest as the most important variables, demonstrating robust agreement across methods.