Table 3.
The Validity of hEtG and other Maternal Biomarkers
| Biomarkers | Sensitivity (%) (95% CI) |
Specificity (%) (95% CI) |
PPV (%) | NPV (%) |
|---|---|---|---|---|
| hEtG ≥ 8 pg/mg | 19.1 (8.6; 34.1) | 86.1 (72.1; 94.7) | 57.1 | 52.1 |
| GGT > 40 U/L | 20.0 (9.1; 35.7) | 97.6 (87.4; 99.9) | 88.9 | 56.1 |
| %dCDT > 2.0%a | 5.0 (0.6; 16.9) | 100 (91.6; 100) | 100 | 52.5 |
| %dCDT > 1.7%a | 22.5 (10.8; 38.5) | 71.4 (55.4; 84.3) | 42.8 | 49.2 |
| uEtG ≥ 25 ng/mL | 4.9 (0.6, 16.5) | 97.6 (87.4, 99.9) | 66.7 | 51.2 |
| uEtS ≥ 7 ng/mL | 7.3 (1.5, 19.9) | 97.6 (87.4; 99.9) | 75.0 | 51.9 |
| PEth > 8 ng/mL | 17.5 (7.34; 32.8) | 100 (91.8, 100) | 100 | 56.6 |
| Combinations | ||||
| hEtG + uEtG | 22.0 (10.6; 37.6) | 83.3 (68.6; 93.0) | 56.2 | 52.2 |
| hEtG + uEtS | 24.3 (12.4; 40.3) | 83.3 (68.6; 93.0) | 58.8 | 53.0 |
| hEtG + GGT | 32.5 (18.6; 49.1) | 83.3 (68.6; 93.0) | 65.0 | 56.4 |
| hEtG + %dCDT > 2.0% | 22.5 (10.8; 38.5) | 85.7 (71.5; 94.6) | 60.0 | 53.7 |
| hEtG + %dCDT > 1.7% | 37.5 (22.7; 54.2) | 59.5 (43.3; 74.4) | 46.9 | 50.0 |
| hEtG + PEth | 27.5 (14.6; 43.9) | 86.0 (72.1; 94.7) | 64.7 | 56.1 |
| hEtG+%dCDTb+GGT | 50.0 (33.8; 66.2) | 56.1 (39.7; 71.5) | 52.6 | 53.5 |
| hEtG+GGT+PEth | 37.5 (22.7; 54.2) | 83.4 (68.6; 93.0) | 68.2 | 58.3 |
| hEtG+PEth+%dCDTb | 42.5 (27.0; 59.1) | 59.5 (43.3; 74.4) | 50.0 | 52.1 |
PPV = positive predictive value; NPV = negative predictive value
a
Both a traditional cut-off for %dCDT > 1.7% and a recently proposed cutoff for pregnant women of >2.0% are presented.
b
%d CDT > 1.7% was used in this battery.