TABLE 1.
Sensitivities, specificities, positive predictive values, and negative predictive values for treatment failure at different viral load thresholds
| Threshold | Sensitivity (% [95% CI]) | Specificity (% [95% CI]) | PPV (% [95% CI]) | NPV (% [95% CI]) | Downward misclassification (%) | Upward misclassification (%) |
|---|---|---|---|---|---|---|
| TND/BLQa | 77 (69.4–85.5) | 100 (97.1–100) | 100 (96.8–100) | 78.5 (71.2–84.6) | 23 | 0 |
| 1,000 copies/ml | 92.7 (88.6–96.6) | 100 (97.6–100) | 100 (96.8–100) | 94.3 (89.5–97.4) | 7.30 | 0 |
| 5,000 copies/mlb | 70.9 (61.8–79) | 100 (97.6–100) | 100 (95.7–100) | 82 (75.8–87.2) | 29.10 | 0 |
a
TND, target not detected; BLQ, below the limit of quantification.
b
Sensitivities and specificities were calculated using both a plasma and DBS threshold of 5,000 copies/ml for the definition of treatment failure.