The post hoc analyses were performed and interpreted according
to the statistical rules applied to the IgG immunogenicity
analyses as described in the original publication [1]. For the 13
serotypes contained in PCV13, the serotype-specific OPA titers
were logarithmically transformed for analysis. Geometric mean
titers (GMTs) were calculated. Corresponding 2-sided 95% CIs were
constructed by back transformation of the CIs for the mean of
the logarithmically transformed assay results, which were computed
using the Student’s t distribution. For the GMT ratio, CIs
were computed using the Student’s t distribution for the mean
difference of the measures on the log scale. Noninferiority was
declared if the lower limit of the 2-sided 95% CI for the GMT ratio
(PCV13 + TIV:PCV13) was >0.5 (2-fold criterion). Results were considered
statistically significantly lower, if the upper limit of the 95%
CI for the GMT ratio was