Figure 7. Analysis of age and pre-vaccine peptide reactivity can predict effective neutralization outcome.

(a,b) Tables showing peptides selected in a multivariate prediction model that identified vaccine recipients as upper or lower quartile responders with respect to H1N1 (a) and H3N2 (b) cPost neutralization titer verified using leave-one-out (LOO) cross-validation. The accuracy of using age alone or the model presented in a and b for prediction of good (upper quartile cPost titer) or poor (lower quartile cPost titer) response to vaccine is shown below. Color scale indicates direction and magnitude of the regression coefficient (β) for each element in a and b. (c) Peptides selected in multivariate prediction models of H1N1 cPost-vaccine titer with no age penalty, or increasing age penalty (increasing α age value) using the elastic net method (see methods). Black bars indicate adjacent peptides (overlapping sequence) selected in models using age penalty.