Assay and vaccine group | Serogroup C | Serogroup Y | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|

n^{b} | AT n | AT% | OR | 95% CI | P value^{c} | n^{b} | AT n | AT% | OR | 95% CI | P value^{c} | |

IgG | ||||||||||||

Group 1 (ref group), MenACWY only | 33 | 8 | 24 | 1.00 (ref) | 0.007 | 23 | 10 | 43 | 1.00 (ref) | <0.001 | ||

Group 2, Plus Tdap only | 22 | 15 | 68 | 6.7 | 2.0–22 | 0.002 | 10 | 8 | 80 | 5.2 | 0.9–30 | 0.066 |

Group 3, Plus 4, not Tdap/IPV | 90 | 29 | 32 | 1.5 | 0.6–3.7 | 0.394 | 50 | 36 | 72 | 3.3 | 1.2–9.4 | 0.022 |

Group 4, Plus 4, not Tdap | 133 | 56 | 42 | 2.3 | 1.0–5.4 | 0.064 | 79 | 71 | 90 | 12 | 3.8–35 | <0.001 |

rSBA | ||||||||||||

Group 1 (ref group), MenACWY only | 30 | 14 | 47 | 1.00 (ref) | 0.001 | 17 | 9 | 53 | 1.00 (ref) | 0.114 | ||

Group 2, Plus Tdap only | 20 | 19 | 95 | 22 | 2.6–183 | 0.005 | 14 | 10 | 71 | 2.2 | 0.5–1.0 | 0.297 |

Group 3, Plus 4, not Tdap/IPV | 65 | 50 | 77 | 3.8 | 1.5–9.6 | 0.004 | 60 | 47 | 78 | 3.2 | 1.0–10 | 0.043 |

Group 4, Plus 4, not Tdap | 116 | 92 | 79 | 4.4 | 1.9–10 | 0.001 | 79 | 64 | 81 | 3.8 | 1.3–11 | 0.018 |

↵a Unadjusted logistic regressions with odds ratios are shown for the association of the MenACWY-only group and each of the other vaccine groups. Significant

*P*values are in bold; the alpha was 0.05 for the significance of the parameter values within each model. Abbreviations: AT*n*and AT%, number and percentage, respectively, of subjects who were below the immunologic threshold at baseline and at or above the threshold postvaccination; CI, confidence interval; IgG, immunoglobulin G; IPV, inactivated polio vaccine; MenACWY, tetravalent meningococcal conjugate vaccine A, C, W, and Y; OR, odds ratio; rSBA, rabbit complement serum bactericidal assay; ref, reference; Tdap, tetanus-diphtheria-acellular pertussis vaccine.↵b

*n*includes only subjects with baseline concentrations/titers below immunologic thresholds. The immunologic threshold was defined as a change in IgG concentration of ≥2 μg/ml or rSBA titer of ≥8.↵c Overall

*P*value for the variable “vaccine group.” This tested the null hypothesis that vaccine group was a significant predictor of change in attaining threshold. The alpha was adjusted to 0.0125 to account for the four hypothesis tests.