Table 4.
Diagnostic accuracy of ultrasound measurements of head circumference for prenatal assessment of microcephaly.
| Cut-off | −3 SD | −4 SD | −5 SD |
|---|---|---|---|
| Number of cohorts | 218, 19 | 218, 19 | 218, 19 |
| Number of comparisons | 45 | 45 | 45 |
| Diagnostic odds ratio | 12.7 (2.1–76.5), I2 = 0% | 25.3 (3.7–171.6), I2I2 = 0% | 48.0 (4.8–481.5), I2 = 0% |
| AUC | 0.84 | 0.88 | 0.68 |
| Sensitivity | 0.84 (0.36–0.98) | 0.68 (0.33–0.90) | 0.58 (0.30–0.82) |
| Specificity | 0.70 (0.34–0.91) | 0.91 (0.74–0.97) | 0.97 (0.83–1.00) |
| Positive likelihood ratio | 2.6 (0.88–8.4) | 7.6 (2.1–25.7) | 19.3 (3.0–126.3) |
| Negative likelihood ratio | 0.24 (0.030–1.1) | 0.35 (0.11–0.76) | 0.43 (0.19–0.74) |
| PPV (general pregnancy) | 0.00075 | 0.00215 | 0.00548 |
| NPV (general pregnancy) | 0.99993 | 0.99990 | 0.99988 |
| PPV (ZIKV-infected pregnancy) | 0.0262 | 0.0676 | 0.1564 |
| NPV (ZIKV-infected pregnancy) | 0.9978 | 0. 9966 | 0.9959 |
Parentheses indicate 95% CI. Pre-test probabilities, i.e. incidence of microcephaly among general pregnancies and ZIKV-infected pregnancies were estimated as 0.0285% and 0.95%, respectively.