Neurological impairments at 8 years of age for the 1991–92 cohorts
| ELBW, n = 224 | NBW, n = 223 | |
|---|---|---|
| ELBW, extremely low birthweight; NBW, normal birthweight. | ||
| *χ2 = 20.4, p<0.0001; †increasing severity of CP between groups, χ2trend = 17.6, p<0.0001; ‡χ2 = 1.3, p = 0.25, not significant; §mean difference −10.0, 95% confidence interval −12.8 to −7.1, p<0.0001; ¶increasing severity of intellectual impairment between groups, χ2trend = 38.8, p<0.0001; **two children without cognitive tests excluded. | ||
| Cerebral palsy, n (%) | 24 (10.7) | 1 (0.4)* |
| Cerebral palsy, severity | ||
| Nil, n (%) | 200 (89.3) | 222 (99.6)† |
| Mild, n (%) | 12 (5.4) | 0 (0) |
| Moderate, n (%) | 4 (1.8) | 1 (0.4) |
| Severe, n (%) | 8 (3.6) | 0 (0) |
| Blindness, n (%) | 3 (1.3) | 0 (0)‡ |
| Deafness, n (%) | 3 (1.3) | 0 (0)‡ |
| Full scale IQ, mean (SD) | 94.9 (15.8), n = 209 | 104.9 (14.1), n = 220§ |
| Intellectual impairment, severity | n = 224 | n = 221¶** |
| Nil, n (%) | 131 (58.5) | 193 (87.3) |
| Mild, n (%) | 56 (25.0) | 19 (8.6) |
| Moderate, n (%) | 18 (8.0) | 5 (2.3) |
| Severe, n (%) | 19 (8.5) | 4 (1.8) |