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) |
The study was carried out in Azaguié M’Bromé, south Côte d’Ivoire between June and September 2011 and focussed on a subset of 118 preschool-aged children (<6 years of age).
CI, confidence interval.