Table 3.

Comparison of ELISA concentrations between laboratories and laboratory-to-consensus assigned values for WHO calibration sera

Lab no. (n)StatisticValue for laba:
12345
1 (156)Accuracy (Ca)1.00.9940.9860.9930.995
Precision (r)1.00.9890.9310.9950.982
CCCb (rc)1.00.9820.9180.9890.977
CCC 95% CI0.977, 0.9860.892, 0.9380.986, 0.9910.969, 0.982
2 (156)Accuracy (Ca)1.00.9981.0000.978
Precision (r)1.00.9020.9880.989
CCC (rc)1.00.9000.9880.967
CCC 95% CI0.866, 0.9260.984, 0.9910.960, 0.973
3 (156)Accuracy (Ca)1.00.9980.964
Precision (r)1.00.9240.915
CCC (rc)1.00.9220.882
CCC 95% CI0.894, 0.9420.849, 0.908
4 (156)Accuracy (Ca)1.00.977
Precision (r)1.00.983
CCC (rc)1.00.961
CCC 95% CI0.952, 0.968
5 (156)Accuracy (Ca)1.0
Precision (r)1.0
CCC (rc)1.0
Consensus value (780)Accuracy (Ca)1.0000.9950.9900.9950.993
Precision (r)0.9940.9820.9440.9910.985
CCC (rc)0.9940.9770.9340.9860.978
CCC 95% CI0.993, 0.9940.974, 0.9800.926, 0.9420.984, 0.9870.975, 0.981
  • a Consensus ELISA concentrations were estimated within a serotype by using a random-effects ANOVA model. Predicted ELISA concentrations were obtained for each laboratory by sample within a serotype for each of the replicate observations by using a random-effects ANOVA model.

  • b CCC, concordance correlation coefficient.