Vaccine | Serotype | n^{b} | Correlation between assays^{a} | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|

Flow and killing | ELISA and killing | Flow and ELISA | |||||||||

r | P^{f} | S^{d} | r | P | S | r | P | S | |||

23-valent PS | 6A | 23 | 0.58 | 0.01 | 0.16 | 0.17 | 0.01 | 1.34 | 0.60 | 0.01 | 0.48 |

6B | 23 | 0.87 | 0.001 | 0.56 | 0.54 | 0.05 | 0.54 | 0.49 | 0.05 | 0.32 | |

19F | 23 | 0.06 | NS^{e} | 0.10 | 0.22 | NS | 0.55 | 0.14 | NS | 0.44 | |

Bivalent conjugate | 23F | 46^{c} | 0.91 | 0.01 | 0.47 | 0.87 | 0.01 | 1.34 | 0.98 | 0.001 | 0.64 |

Tetravalent conjugate | 6B | 34 | 0.77 | 0.001 | 0.41 | 0.90 | 0.001 | 1.62 | 0.79 | 0.001 | 0.76 |

19F | 40 | 0.65 | 0.01 | 0.30 | 0.87 | 0.01 | 1.07 | 0.65 | 0.05 | 0.37 | |

23F | 40 | 0.79 | 0.001 | 0.61 | 0.91 | 0.001 | 1.33 | 0.75 | 0.001 | 0.84 |

↵a The correlation coefficient (

*r*) was calculated by Pearson's bivariate linear correlation analysis.↵b

*n*is the total number of analyzed antisera per vaccine. For the PS vaccine, only postvaccination antisera were analyzed, whereas for the conjugate vaccines pre- and postvaccination antisera were combined for correlation analysis.↵c For the killing assay, titers were obtained for 14 antisera only. Therefore, correlations between killing assay and ELISA flow assay and ELISA were calculated for these corresponding 14 antisera.

↵d The slope (

*S*) of the fitted linear curve,*Y*=*Sx*+*b*, was calculated by linear regression analysis.↵e NS, not significant

↵f

*P*is less than the values given.