TABLE 3.

Qualitative agreement between the reference NT and in-house or commercial ELISA kitsa

Lab test result (IU/ml)No. of samples with NT result:
Positive (≥0.1 IU/ml)Equivocal (0.01-09 IU/ml)Negative (<0.01 IU/ml)
Lab III in-house ELISA
    Positive (≥0.1)674020
    Negative (<0.1)1058
Lab XI in-house ELISA
    Positive (≥0.1)6991
    Negative (<0.1)63527
Lab X Serion
    Positive (>1.0)500
    Equivocal (0.1-1.0)4693
    Negative (<0.1)243623
Lab IV NovaLisa
    Positive (≥0.1)4971
    Equivocal (0.01-0.09)283824
    Negative (<0.01)003
Lab VII Euroimmun
    Positive (>1.0)300
    Equivocal (0.1-1.0)2941
    Negative (<0.1)454127
Lab I Virotech
    Positive (>1.0)600
    Equivocal (0.1-1.0)64144
    Negative (<0.1)73124
Lab V Virotech
    Positive (>1.0)700
    Equivocal (0.1-1.0)5872
    Negative (<0.1)123826
Lab I VaccZyme
    Positive (>0.149)68131
    Retest (0.1-0.149)b6122
    Negative (<0.1)32025
Lab IV VaccZyme
    Positive (>0.149)60112
    Retest (0.1-0.149)b15152
    Negative (<0.1)21924
Lab VI VaccZyme
    Positive (>0.149)64111
    Retest (0.1-0.149)b10162
    Negative (<0.1)31825
Lab IX VaccZyme
    Positive (>0.149)75181
    Retest (0.1-0.149)b2187
    Negative (<0.1)0920
  • a According to the reference lab IX NT, 77/150 samples were positive, 45 samples were equivocal, and 28 samples were negative. Labs X, XI, and XII tested only 146, 147, and 140 samples, respectively.

  • b “Retest,” sample to be retested.