TABLE 3.
Comparisons of serologic tests for diagnosis of WNV infections using sera of patients from Colorado and Cohen's kappa analysis
| Comparisona | No. positive in both tests | No. positive in PRNT90 and negative in ELISA | No. positive in ELISA and negative in PRNT90 | No. negative in both tests | Cohen's kappa analysis (95% CI) |
|---|---|---|---|---|---|
| IgM ELISA vs WNV PRNT90 | 292 | 0 | 0 | 74 | 1.0000 (1.0000-1.000) |
| WNV b-ELISA vs WNV PRNT90 | 265 | 27 | 6 | 68 | 0.7473 (0.6666-0.8280) |
a
Cutoff values for tests: for PRNT90, WNV titer of ≥1:10; for IgM ELISA, positive/negative ratio of ≥3.0; for b-ELISA WNV, 8%.