Table 4.
Subject Characteristics by Four-Year VIQ Groups and Total
| Characteristic, median (range) or n (%) | VIQ < 70 (n=6) | VIQ 70–84 (n=14) | VIQ ≥ 85 (n=43) | p-value* | Total (n=64**) |
|---|---|---|---|---|---|
| Male gender | 4 (67%) | 9 (64%) | 21 (49%) | 0.5 | 35 (55%) |
|
| |||||
| Gestational age, weeks | 40 (35–42) | 39 (36–42) | 40 (36–42) | 0.8 | 40 (35–42) |
|
| |||||
| Cesearean section | 4 (67%) | 5 (36%) | 16 (37%) | 0.4 | 26 (41%) |
|
| |||||
| Birth weight, grams | 3605 (2350–5120) | 3152.5 (2020–4490) | 3354 (2040–4575) | 0.4 | 3330 (2020–5120) |
|
| |||||
| Birth head circumference, cm | 35.5 (31–36) | 34 (32.5–36) | 35 (31–38) | 0.3 | 35 (31–38) |
|
| |||||
| 5-minute Apgar | 4.5 (4–6) | 5 (3–8) | 5 (1–9) | 0.6 | 5 (1–9) |
|
| |||||
| Encephalopathy score (0–6)† | 3 (2–6) | 4 (1–6) | 3 (0–6) | 0.2 | 3 (0–6) |
|
| |||||
| Resuscitation score (1–6)‡ | 4.5 (4–6) | 4.5 (3–5) | 4 (2–6) | 0.2 | 4 (2–6) |
|
| |||||
| Neonatal seizures | 1 (17%) | 4 (29%) | 5 (12%) | 0.2 | 10 (16%) |
|
| |||||
| PIQ | 87 (71–102) | 88 (70–101) | 109 (76–141) | 0.0001 | 100.5 (70–141) |
|
| |||||
| Ethnicity | |||||
| American Indian/Native Alaskan | 1 (2%) | ||||
| Asian/Pacific Islander | 14 (22%) | ||||
| Black, non-Hispanic | 2 (3%) | ||||
| Hispanic | 15 (23%) | ||||
| White, non-Hispanic | 32 (50%) | ||||
*
p-values were obtained using Fisher’s exact test (n) or Kruskal-Wallis test (median), and refer to comparison across the 3 groups
**
1 subject not in included in VIQ groups because no VIQ was measured
†
The severity of clinical brain dysfunction was graded from 0 (no clinical encephalopathy) to 6 (severe clinical encephalopathy) using a validated score on the basis of alertness, feeding, tone, respiratory status, reflexes, and seizure activity.21
‡
The amount of resuscitation at birth was graded from 1 (no intervention) to 6 (endotracheal intubation with ventilation and sodium bicarbonate with or without epinephrine) using a previously validated score.10