Table 1.
Comparison of six treponemal assays to the FTA assay using serum specimensa
| Assay and result | FTA result (no. of samples) |
% Sensitivity (95% CI) | % Specificity (95% CI) | % Agreement (95% CI) | κ value | |
|---|---|---|---|---|---|---|
| Positive | Negative | |||||
| BioPlex syphilis IgGb | ||||||
| Positive | 94 | 3 | 96.9 (90.9, 99.3) | 98.5 (95.6, 99.7) | 98.0 (95.6, 99.2) | 0.96 |
| Negative | 3 | 202 | ||||
| TP-PA | ||||||
| Positive | 93 | 5 | 95.9 (89.5, 98.7) | 97.6 (94.3, 99.1) | 97.0 (94.4, 98.5) | 0.93 |
| Negative | 4 | 201 | ||||
| Trep-Chek IgG | ||||||
| Positive | 93 | 1 | 95.9 (89.5, 98.7) | 98.5 (95.6, 99.7) | 97.7 (95.2, 99.0) | 0.95 |
| Negative | 4 | 203 | ||||
| Equivocal | 0 | 2 | ||||
| Trep-Sure | ||||||
| Positive | 94 | 4 | 96.9 (90.9, 99.3) | 94.7 (90.6, 97.1) | 95.4 (92.3, 97.3) | 0.90 |
| Negative | 3 | 195 | ||||
| Equivocal | 0 | 7 | ||||
| Trep-ID | ||||||
| Positive | 94 | 2 | 96.9 (90.9, 99.3) | 99.0 (96.3, 100) | 98.4 (96.1, 99.4) | 0.96 |
| Negative | 3 | 204 | ||||
| ViraBlot IgG | ||||||
| Positive | 91 | 2 | 93.8 (86.9, 97.4) | 98.5 (95.6, 99.7) | 97.0 (94.4, 98.5) | 0.93 |
| Negative | 5 | 203 | ||||
| Equivocal | 1 | 1 | ||||
a
A total of 303 samples were analyzed.
b
Only 302 samples were analyzed for the BioPlex, as one sample did not yield a result due to an instrument error code.