TABLE 2.
Comparison of BV molecular assays to positive and negative NS Gram stain for 92 specimensa
| Assay | TP | FP | TN | FN | Sensitivity (%) | Specificityb (%) | PPV (%) | NPV (%) |
|---|---|---|---|---|---|---|---|---|
| Aptima IVD | 36 | 4 | 48 | 4 | 90.0 (76.4–96.6) | 92.3 (81.3–97.5) | 90.0 (76.4–96.6) | 92.3 (81.2–87.5) |
| BD Affirm | 35 | 19 | 33 | 5 | 87.5 (73.4–95.0) | 63.4 (49.8–75.2) | 64.8 (51.5–76.2) | 86.8 (72.2–94.7) |
| Hologic ASR | 33 | 8 | 44 | 7 | 82.5 (67.7–91.6) | 84.6 (72.2–92.3) | 80.5 (65.7–90.0) | 86.3 (74.0–93.5) |
a
The 19 specimens with intermediate NSs (4–6) were excluded. BV, bacterial vaginosis; NS, Nugent score; TP, true positive; FP, false positive; TN, true negative; FN, false negative; PPV, positive predictive value; NPV, negative predictive value. Values in parentheses are 95% confidence intervals.
b
The specificity of Aptima IVD was higher than BD Affirm (P = 0.0003).