Bar graph of IR1/IR2 signature synergy. Green bars (left) show the coefficients for single-variable logistic regression models of EFS24 including either IR1 or IR2 alone. Purple bars (right) show their coefficients when included in a combined 2-variable model. Separate results are shown for both the training and validation cohorts. The increased magnitude of the coefficients in the combined model shows that they act synergistically. Error bars indicate the estimated standard error of the coefficients from the logistic models.