Table 9.

Illustrative effect of European immunoblot interpretation rules on percent sensitivity and specificitya

RulebNo. of bandsAverageLaboratory ALaboratory BLaboratory CLaboratory D (B. afzelii)Laboratory D (B. garinii)Laboratory E (no IgM OspC)Laboratory F
% Sensc% Specd% Sens% Spec% Sens% Spec% Sens% Spec% Sens% Spec% Sens% Spec% Sens% Spec% Sens% Spec
1268918592599573785599539981917380
32910045100251003399191001110034993899
2275898592819473786198579988858279
3499854995399419943993710064975097
3287729273878896447592728995709547
369927695669871825799509984918180
4277888689819474766797579989848279
3569866995699479954994010067975697
5287729371888896468092748995699547
371928094679873816298519985918180
6279868687859278766897579989848867
3629673956099569956994210068967887
7290709369918696448392748995699739
374908292699877816298579985918869
4589769974999559954993810066977787
  • a Examples of the “best” qualifying rules (70% sensitivity and 90% specificity) for each laboratory are given in boldface italic type.

  • b Rules 1 and 3 were eliminated because they did not provide an adequate combination of sensitivity and specificity for all laboratories.

  • c Sens, sensitivity was calculated by combining data for IgG and IgM.

  • d Spec, specificity was calculated by combining data for potential cross-reactor and healthy individuals' sera.