Table 1 The characteristics and classification of clinical specimens
From: The effect of hemolysis on quality control metrics for noninvasive prenatal testing
Classification | Visual inspection | Number | Hemoglobin level (g/L) | Maternal age in years (range) | Gestational week (range) | P1 | P2 |
|---|---|---|---|---|---|---|---|
Group I |
| 53 | [0, 1] | 30 (19–45) | 16+1 (12+0–28+0) | – | – |
Group II |
| 97 | (1, 2] | 30 (19–50) | 16+0 (12+1–27+3) | 0.972 | 0.623 |
Group III |
| 30 | (2, 4] | 30 (19–39) | 15+4 (12+0–22+1) | 0.904 | 0.541 |
Group IV |
| 25 |  > 4 | 31 (22–41) | 16+2 (12+0–19+6) | 0.391 | 0.517 |
