Table 4 Screening performance of the studied facial ultrasound markers for the fetuses with Down syndrome
| Â | PT | NBL | PT/NBL ratio | NBL/ PT ratio |
|---|---|---|---|---|
Sensitivity (%) | 91 | 100 | 100 | 100 |
Specificity (%) | 93 | 92 | 92 | 92 |
False positive (%) | 6.76 | 7.6 | 6.5 | 7.6 |
False negative (%) | 9.0 | 0 | 0 | 0 |
Positive predictive value | 30 | 30 | 30 | 30 |
Negative predictive value | 100 | 100 | 100 | 100 |
Positive likelihood ratio | 13.44 | 13.08 | 13.08 | 13.08 |
Negative likelihood ratio | 0.14 | 0.00 | 0.00 | 0.00 |
AUC | 0.921 | 0.962 | 0.968 | 0.969 |