Table A1.
The relationship between Z score and fetal fraction in common trisomies by NIPS.
| Common Trisomies | Basic Information (All) | Basic Information of Male-Population (cf-DNA% Calculated by Y) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Z Score | n | NIPS-TP | NIPS-FP | n | NIPS-TP | NIPS-FP | |||||||||
| n (Ratio %) | Mean Z Score |
n (Ratio %) | Mean Z Score |
n (Ratio %) | Mean Z Score |
Mean FF% (Range) |
p-Value | n (Ratio %) | Mean Z Score |
Mean FF% (Range) |
p Value | ||||
| Trisomy 21 | 3 ≤ Z < 6 | 41 | 15 (36.59) | 4.57 | 26 (63.41) | 4.63 | 23 | 11 (47.83) | 4.66 | 8.29 (4.01–13.03) | <0.001 | 12 (52.17) | 4.83 | 10.01 (4.37–16.11) | <0.05 |
| 6 ≤ Z < 10 | 79 | 70 (88.61) | 7.98 | 9 (11.39) | 7.55 | 51 | 45 (88.24) | 7.95 | 10.4 (6.05–33.04) | 6 (11.76) | 7.65 | 14.26 (7.32–22.00) | |||
| 10 ≤ Z < 16 | 149 | 147 (98.66) | 12.93 | 2 (1.34) | 14.45 | 79 | 79 (100.00) | 12.85 | 14.42 (8.52–22.36) | 0 (0.00) | ― | ― | |||
| Z ≤ 16 | 90 | 90 (100.00) | 21.28 | 0 | ― | 44 | 44 (100.00) | 21.06 | 21.26 (10.55–34.86) | 0 | ― | ― | |||
| Total | 359 | 322 | 37 | 197 | 179 | 18 | |||||||||
| Trisomy 18 | 3 ≤ Z < 6 | 26 | 12 (46.15) | 4.69 | 14 (53.85) | 4.14 | 10 | 5 (50.00) | 4.22 | 7.41 (3.27–15.86) | <0.002 | 5 (50.00) | 4.54 | 11.95 (6.73–14.94) | |
| 6 ≤ Z < 10 | 27 | 26 (96.30) | 8.12 | 1 (3.70) | 6.27 | 12 | 11 (91.67) | 8.09 | 8.72 (4.61–16.58) | 1 (8.33) | 6.27 | 6.9 | / | ||
| 10 ≤ Z < 16 | 34 | 33 (97.06) | 12.57 | 1 (2.94) | 11.52 | 14 | 14 (100.00) | 12.21 | 11.95 (8.71–22.47) | 0 (0.00) | ― | ― | |||
| Z ≥ 16 | 13 | 13 (100.00) | 20.9 | 0 | ― | 7 | 7 (100.00) | 20.07 | 15.94 (12.52–22.17) | 0 | ― | ― | |||
| Total | 100 | 84 | 16 | 43 | 37 | 6 | |||||||||
| Trisomy 13 | 3 ≤ Z < 6 | 23 | 7 (30.43) | 4.91 | 16 (69.57) | 4.44 | 8 | 2 (25.00) | 4.53 | 6.95 (3.10–10.80) | =0.143 | 6 (75.00) | 4.84 | 13.78 (7.27–22.19) | =0.869 |
| 6 ≤ Z < 10 | 21 | 12 (57.14) | 7.76 | 9 (42.86) | 7.19 | 11 | 7 (63.64) | 7.72 | 8.53 (5.14–12.75) | 4 (36.36) | 6.6 | 14.35 (10.58–20.59) | |||
| 10 ≤ Z < 16 | 11 | 10 (90.91) | 12.11 | 1 (9.09) | 10.57 | 7 | 7 (100.00) | 11.82 | 11.24 (6.96–16.47) | 0 (0.00) | ― | ― | |||
| Z ≥ 16 | 2 | 1 (50.00) | 16.66 | 1 (50.00) | 17.14 | 1 | 0 (0.00) | ― | ― | 1 (100.00) | 17.14 | 22.6 | |||
| Total | 57 | 30 | 27 | 27 | 16 | 11 | |||||||||
NIPS, noninvasive prenatal screening; TP, true positive; FP, false positive; FF, fetal fraction.