Figure 1From: Factors associated with maintenance of antibody responses to influenza vaccine in older, community-dwelling adultsPredicted probability of seroprotection at S2 for each vaccine strain by age at enrollment and pre-vaccination HAI titer. Each graph shows the probability of seroprotection predicted by logistic regression models for H1N1 (first column), H3N2 (second column) and B (third column) by the age at enrollment (first row) or the pre-vaccination HAI titer (second row) 4 weeks post-vaccination.Back to article page