Neurodevelopmental outcomes at 18–24 months
| Infant outcomes at 20–24 months | MRI (n=255)* | Ultrasound (n=255)* |
| Infant age at assessment, median (IQR) | 20.20 (20.00–20.79) | 20.20 (20.00–20.50) |
| Gross Motor Function Classification Scale, n (%) | ||
| No abnormality or grade 1 | 221 (92.86) | 229 (93.09) |
| Grade 2 | 8 (3.36) | 12 (4.88) |
| Grade 3 | 3 (1.26) | 2 (0.81) |
| Grade 4 | 4 (1.68) | 2 (0.81) |
| Grade 5 | 2 (0.84) | 1 (0.41) |
| Missing | 17 | 9 |
| Bayley-III motor composite score, mean (SD) | 93.19 (14.02) | 95.04 (12.62) |
| Missing, n | 17 | 9 |
| Bayley-III cognitive composite score, mean (SD) | 91.16 (14.14) | 92.91 (13.67) |
| Missing, n | 17 | 9 |
| Bayley-III language composite score, mean (SD) | 89.23 (17.73) | 91.11 (17.15) |
| Missing, n | 17 | 9 |
| PARCA-R composite, mean (SD) | 45.20 (24.78) | 48.02 (23.97) |
| Missing, n | 21 | 10 |
| M-CHAT failing two or more critical items, n (%) | 85 (35.42) | 67 (27.24) |
| Missing, n | 15 | 9 |
*Number of infants in each group (MRI and ultrasound).
Bayley-III, Bayley Scales of Infant Development III; M-CHAT, modified checklist for autism in toddlers; PARCA-R, parent report of children’s abilities-revised.