Table 1.
Sensitivity and Specificity of an Rapid Diagnostic Test in Detecting Malaria Infection, as Defined by Positive Microscopy or a Positive Polymerase Chain Reaction Assay in Peripheral Blood, at Initial Antenatal Clinic Visits in Pregnant Women in Four West African Countries
| Gravidity | PCR or Blood Slide /RDT |
RDT Sensitivity % (95% CI) | RDT Specificity % (95% CI) | Number Positives With Density Result | Geometric Mean Density by Microscopya, Parasites per µL (95% CI) | ||||
|---|---|---|---|---|---|---|---|---|---|
| +/+ | +/− | −/+ | −/− | ||||||
| Burkina Faso | All | 348 | 35 | 10 | 160 | 90.9 (87.5, 93.6) | 94.1 (89.4, 97.1) | 591 | 1054.5 (951.5, 1168.7) |
| Primigravidae | 208 | 14 | 2 | 57 | 93.7 (89.6, 96.5) | 96.6 (88.3, 99.6) | 360 | 1372.3 (1213.1, 1552.3) | |
| Secundigravidae | 137 | 21 | 8 | 103 | 86.7 (80.4, 91.6) | 92.8 (86.3, 96.8) | 221 | 683.2 (576.5, 809.7) | |
| Ghana | All | 308 | 39 | 23 | 222 | 88.8 (85.0, 91.9) | 90.6 (86.2, 94.0) | 618 | 1950.0 (1760.8, 2159.6) |
| Primigravidae | 193 | 10 | 15 | 99 | 95.1 (91.1, 97.6) | 86.8 (79.2, 92.4) | 402 | 2403.9 (2127.7, 2715.9) | |
| Secundigravidae | 113 | 29 | 8 | 122 | 79.6 (72.0, 85.9) | 93.8 (88.2, 97.3) | 214 | 1314.8 (1104.9, 1564.6) | |
| Mali | All | 165 | 25 | 15 | 283 | 86.8 (81.2, 91.3) | 95.0 (91.8, 97.2) | 275 | 1343.5 (1131.4, 1595.3) |
| Primigravidae | 118 | 10 | 11 | 168 | 92.2 (86.1, 96.2) | 93.9 (89.3, 96.9) | 201 | 1431.5 (1169.6, 1752.1) | |
| Secundigravidae | 47 | 15 | 4 | 115 | 75.8 (63.3, 85.8) | 96.6 (91.6, 99.1) | 74 | 1130.6 (812.2, 1573.8) | |
| The Gambia | All | 48 | 33 | 5 | 463 | 59.3 (47.8, 70.1) | 98.9 (97.5, 99.7) | 93 | 398.4 (307.0, 517.2) |
| Primigravidae | 35 | 20 | 1 | 246 | 63.6 (49.6, 76.2) | 99.6 (97.8, 100.0) | 63 | 399.2 (291.3, 547.0) | |
| Secundigravidae | 13 | 13 | 4 | 217 | 50.0 (29.9, 70.1) | 98.2 (95.4, 99.5) | 30 | 397.0 (242.5, 649.9) | |
A true positive has been defined as a positive PCR or blood slide result, a true negative as a PCR and blood slide negative result.
Abbreviations: CI, confidence interval; PCR, polymerase chain reaction; RDT, rapid diagnostic test.
a Geometric mean parasite density is based on individuals who tested positive by blood slide: ie, this it does not include low density infections that were missed by microscopic examination.