Table 2 Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of each diagnostic assay using quadruplicate Kato-Katz thick smears as the reference standard for S. mansoni diagnosis and two urine filtrations as the reference standard for S. haematobium diagnosis
Four Kato-Katz as reference standard | Sensitivity (95% CI) | Specificity (95% CI) | NPV (95% CI) | PPV (95% CI) |
|---|---|---|---|---|
Single Kato-Katz thick smear (day 1) | 50.0 (29.6–70.4) | 100 (95.1–100) | 88.7 (80.7–93.8) | 100 (69.9–100) |
Duplicate Kato-Katz thick smears | 75.0 (52.9–89.4) | 100 (95.1–100) | 94.0 (86.9–97.5) | 100 (69.2–100) |
Single POC-CCA cassette (day 1) | 75.0 (52.9–89.4) | 53.2 (42.7–63.5) | 89.3 (77.4–95.6) | 29.0 (18.6–42.1) |
Duplicate POC-CCA cassettes | 75.0 (52.9–89.4) | 46.8 (36.5–57.3) | 88.0 (75.0–95.0) | 26.4 (16.8–38.8) |
Single SmCTF-RDT | 75.0 (52.9–89.4) | 34.0 (24.8–44.6) | 84.2 (68.1–93.4) | 22.5 (14.2–33.5) |
Two urine filtrations as reference standard | Sensitivity (95% CI) | Specificity (95% CI) | NPV (95% CI) | PPV (95% CI) |
Single urine filtration (day 1) | 66.7 (24.1–94.0) | 100 (95.9–100) | 98.2 (93.2–99.7) | 100 (39.6–100) |
Single SmCTF-RDT | 66.7 (24.1–94.0) | 33.0 (24.6–42.6) | 94.9 (81.4–99.1) | 5.1 (1.6–13.1) |