Table 3.
RDT, LM and qPCR of peripheral blood and detection active P. falciparum placental infection on histology (n = 158)
| Placental infection (histology) | Sensitivity (%) (95 % CI) | Specificity (%) (95 % CI) | PPV (%) (95 % CI) | NPV (%) (95 % CI) | ||
|---|---|---|---|---|---|---|
| Positive (n = 31) | Negative (n = 127) | |||||
| RDT | ||||||
| Positive (n = 21) | 14 | 7 | 45.2 (27.3, 64.0) | 94.5 (89.0, 97.8) | 66.7 (43.0, 85.4) | 87.6 (80.9, 92.6) |
| Negative (n = 137) | 17 | 117 | ||||
| LM | ||||||
| Positive (n = 16) | 14 | 2 | 45.2 (27.3, 64.0) | 98.4 (94.4, 99.8) | 87.5 (61.7, 98.4) | 88.0 (81.5, 92.9) |
| Negative (n = 142) | 17 | 125 | ||||
| qPCR | ||||||
| Positive (n = 15) | 13 | 2 | 41.9 (24.5, 60.9) | 98.4 (94.4, 99.8) | 86.7 (59.5, 98.3) | 87.4 (80.8, 92.4) |
| Negative (n = 143) | 18 | 125 | ||||
| LM + RDT | ||||||
| Positive (n = 25) | 17 | 8 | 54.8 (36.0, 72.7) | 93.7 (88.0, 97.2) | 68.0 (46.5, 85.1) | 89.5 (83.0, 94.1) |
| Negative (n = 133) | 14 | 119 | ||||
Performance characteristics of RDT and LM for detection of active placental malaria on placental histology. RDT rapid diagnostic test, LM light microscopy, qPCR real-time polymerase chain reaction, PPV positive predictive value, NPV negative predictive value. Sensitivities and specificities of RDT, LM and qPCR were not statistically different (all P > 0.05, Liddell’s exact test)