Table 8 Effect of weight correction on risk estimates for a hypothetical 35‐year‐old woman.
| Corrected weight (kg) | |||||||
|---|---|---|---|---|---|---|---|
| 35 | 65 | 95 | |||||
| Basal MoM | LL | LR | LL | LR | LL | LR | |
| Normal | |||||||
| AFP | 1.0 | 0.7191 | 0.5588 | 0.9813 | 0.9287 | 1.3391 | 1.2282 |
| HCG | 1.0 | 0.8177 | 0.6453 | 0.9991 | 0.8928 | 1.2207 | 1.0397 |
| uE3 | 1.0 | 0.8632 | 0.7601 | 0.9911 | 0.9493 | 1.1379 | 1.0452 |
| Risk | 1627 | 1109 | 820 | 1573 | 1657 | 1915 | 2122 |
| Diff LL v LR | 26.05% | −5.34% | −10.9% | ||||
| Down's syndrome | |||||||
| AFP | 0.7 | 0.5034 | 0.3911 | 0.6869 | 0.6501 | 0.9373 | 0.8597 |
| HCG | 2.0 | 1.6354 | 1.2906 | 1.9982 | 1.7856 | 2.4413 | 2.0794 |
| uE3 | 0.7 | 0.6042 | 0.5321 | 0.6937 | 0.6645 | 0.7965 | 0.7317 |
| Risk | 128 | 62 | 36 | 120 | 122 | 200 | 202 |
| Diff LL v LR | 41.93% | −1.66% | −1% | ||||
AFP, αfetoprotein; HCG, human chorionic gonadotropin; LL, log–linear; LR, linear–reciprocal; MoM, multiples of the median; uE3, unconjugated oestriol.