Table 1.
Birth status and demographic characteristics of extremely preterm/extremely low birth weight (EPT/ELBW) and term-born normal birth weight (NBW) groups.
| Characteristic | EPT/ELBW group (n = 111) | NBW group (n = 110) |
|---|---|---|
| Birth status: | ||
| Gestational age in weeks, mean (SD), range | 26 (2) range: 23-31 | >36 |
| Birth weight in grams, mean (SD), range | 818 (176) range: 485-1281 | 3386 (446) range: 2495 - 4508 |
| Neonatal risk factors: | ||
| Bronchopulmonary dysplasia (BPD), n (%) | 54 (49%) | - |
| Neonatal Infection, n (%) | 43 (39%) | - |
| Severely abnormal cranial ultrasound, n (%) | 9 (8%) | - |
| Severe retinopathy of prematurity, n (%) | 17 (16%) | - |
| Early childhood neurodevelopmental status: | ||
| Neurosensory Abnormality, n (%) | 8 (7%) | - |
| Neurodevelopmental Impairment, n (%) | 42 (39%) | - |
| Demographic characteristics: | ||
| Age in years at testing, mean (SD) | 5.92 (.34) | 5.97 (.31) |
| Months in school at testing, mean (SD)a | 4.12 (2.13) | 6.39 (1.72) |
| Age in years at observation, mean (SD)a | 6.16 (.36) | 6.01 (.30) |
| Months in school at observation, mean (SD) | 7.01 (1.71) | 6.94 (1.64) |
| Male sex | 50 (45%) | 50 (46%) |
| African American | 70 (63%) | 60 (55%) |
| Maternal education: | ||
| <high school | 15 (14%) | 13 (12%) |
| High school or GED | 23 (21%) | 16 (15%) |
| >high school | 73 (66%) | 81 (74%) |
| Median family income, mean (SD) | 58 (34) | 56 (24) |
| SES z-score composite, mean (SD) | -.06 (1.04) | .08 (.97) |
Significant group difference, p< .001
Note: BPD defined by supplemental oxygen at 36 weeks corrected age; neonatal infection as septicemia or necrotizing enterocolitis; severe ultrasound abnormality as Grade III/IV intraventricular hemorrhage, periventricular leukomalacia, or ventricular dilation at discharge; severe retinopathy of prematurity as stage 4 or 5 retinopathy or treatment with cryotherapy or laser therapy; neurosensory abnormality as cerebral palsy (6 children), blindness (2 children, 1 with cerebral palsy), or deafness (1 child); neurodevelopmental impairment as any neurosensory abnormality or Mental Development Index of <70 on the Bayley Scales of Infant Development, 2nd edition [38] at 20 months’ corrected age. The SES z-score composite is the average of the sample z scores for maternal education, caregiver occupation (averaged for two-parent households), and census-based median family income in thousands.