Table 2 The screening performance of NIPT for foetal chromosomal abnormalities in twin pregnancies
chromosomal abnormalities | Detected | True positive | False positive | True Negative | Sensitivity (95% CI) | Specificity (95% CI) | PPV (95% CI) |
|---|---|---|---|---|---|---|---|
T21 | 4 | 3 | 1 | 1750 | 100%(29.2–100) | 99.9%(99.7–99.9) | 75%(19.4–99.4) |
T18 | 1 | 0 | 1 | 1753 | - | 99.9%(99.7–99.9) | - |
SCA | 5 | 2 | 2 | 1749 | 100%(15.8–100) | 99.9%(99.6–99.9) | 50%(6.8–93.2) |
MMS | 3 | 0 | 2 | 1751 | - | 99.9%(99.6–99.9) | - |