Table 1.
Sample characteristics.
| VP/VLBW (n = 73) | FT (n = 89) | p value | |||||
|---|---|---|---|---|---|---|---|
| M | SD | Range | M | SD | Range | ||
| Sex(male/female) | 44/29 | 53/36 | 0.93 | ||||
| Age (years) | 26.8 | ± 0.6 | 25.8–28.0 | 26.8 | ± 0.8 | 25.6–28.9 | 0.54 |
| GA (weeks) | 30.4 | ± 2.1 | 25–36 | 39.7 | ± 1.0 | 37–42 | < 0.001 |
| BW (g) | 1305 | ± 311 | 630–2070 | 3372 | ± 468 | 2120–4670 | < 0.001 |
| OPTI neonatal | 9.1 | ± 2.6 | 3–14 | 0.4 | ± 0.7 | 0–3 | < 0.001 |
| SESa (a.u.) | 19/33/21 | 1–3 | 28/41/20 | 1–3 | 0.59 | ||
| Maternal age (years) | 29.3 | ± 4.9 | 16–38 | 29.3 | ± 5.0 | 18–42 | 0.66 |
| Full-scale IQ (a.u.) | 93.9 | ± 11.8 | 64–125 | 102.9 | ± 12.4 | 77–130 | < 0.001 |
Statistical comparisons: Sex, SES with χ2 statistics; age, FS-IQ with two sample t-tests; GA, BW, maternal age with Mann–Whitney-U tests.
BW birth weight, FT full-term, GA gestational age, IQ intelligence quotient, M mean, maternal age maternal age at birth, OPTI standardized optimality scoring system, SD standard deviation, SES socioeconomic status at birth, VP/VLBW very preterm and/or very low birthweight.
a1 = upper class, 2 = middle class, 3 = lower class.