Table 2.
Comparison of seven treponemal assays to the consensus of the test panel using serum specimensa
| Assay and result | Consensus of panel (no. of samples)b |
Sensitivity (%) (95% CI) | Specificity (%) (95% CI) | Agreement (%) (95% CI) | κ value | |
|---|---|---|---|---|---|---|
| Positive | Negative | |||||
| BioPlex syphilis IgGc | ||||||
| Positive | 94 | 3 | 100 (95.3, 100) | 98.6 (95.7, 99.7) | 99.0 (97.0, 99.8) | 0.98 |
| Negative | 0 | 205 | ||||
| FTA | ||||||
| Positive | 94 | 3 | 100 (95.3, 100) | 98.6 (95.7, 99.7) | 99.0 (97.0, 99.8) | 0.98 |
| Negative | 0 | 206 | ||||
| Trep-Chek IgG | ||||||
| Positive | 93 | 1 | 98.9 (93.6, 99.9) | 98.6 (95.7, 99.7) | 98.7 (96.5, 99.6) | 0.97 |
| Negative | 1 | 206 | ||||
| Equivocal | 0 | 2 | ||||
| TP-PA | ||||||
| Positive | 93 | 5 | 98.9 (93.6, 99.9) | 97.6 (94.4, 99.1) | 98.0 (95.6, 99.2) | 0.95 |
| Negative | 1 | 204 | ||||
| Trep-Sure | ||||||
| Positive | 93 | 5 | 98.9 (93.6, 99.9) | 94.3 (90.1, 96.8) | 95.7 (92.7, 97.5) | 0.90 |
| Negative | 1 | 197 | ||||
| Equivocal | 0 | 7 | ||||
| Trep-ID | ||||||
| Positive | 94 | 2 | 100 (95.3, 100) | 99.0 (96.4, 99.9) | 99.3 (97.5, 99.9) | 0.99 |
| Negative | 0 | 207 | ||||
| ViraBlot IgG | ||||||
| Positive | 91 | 2 | 96.8 (90.6, 99.3) | 98.6 (95.7, 99.7) | 98.0 (95.6, 99.2) | 0.95 |
| Negative | 2 | 206 | ||||
| Equivocal | 1 | 1 | ||||
a
A total of 303 samples were analyzed.
b
Consensus of the panel was defined as at least 4 of 7 treponemal IgG or total antibody tests being in agreement.
c
Only 302 samples were analyzed for the BioPlex, as one sample did not yield a result due to an instrument error code.