TABLE 4.
Performance improvement of anti-HTLV-1 Ab assays for CSF by the best cutoff point
| Performance characteristic | CLIA performance at indicated cutoff point |
CLEIA performance at indicated cutoff point |
||
|---|---|---|---|---|
| S/CO of 1.00 (default, adopted from serum) | S/CO of 1.50 (besta) | COI of 1.00 (default, adopted from serum) | COI of 0.14 (besta) | |
| Sensitivity (%) | 96.6 | 94.8 | 69.0 | 89.7 |
| Specificity (%) | 86.4 | 95.5 | 100.0 | 95.5 |
| Accuracy (%)b | 93.8 | 95.0 | 77.5 | 91.3 |
| Likelihood ratioc | 7.1 | 21.1 | NAd | 19.9 |
a
The best cutoff points for anti-HTLV-1 Ab assay in CSF were determined by ROC curve analysis (Fig. 3B).
b
Accuracy was calculated as (true positive + true negative)/(total number).
c
Likelihood ratio was defined as sensitivity/(1 − specificity).
d
NA, not applicable because the specificity of CLEIA at the default cutoff point was 100%.