Table 1.
Characteristics of study subjects included in the developmental analysis compared with those not included.
| Characteristic | Subjects included in the model (n = 98) | Subjects not included in the model (n = 105)a |
|---|---|---|
| Maternal age (years) | 30.2 ± 5.2 | 29.8 ± 5.2 |
| Household income (US$)b,c | 24,564 ± 18,620 | 20,692 ± 16,597 |
| Maternal education (%)c | ||
| < High school | 12.2 | 25.7 |
| High school | 17.4 | 17.1 |
| > High school | 70.4 | 57.1 |
| Ethnicity/race (%) | ||
| Asian | 34.7 | 40.0 |
| Black | 13.3 | 14.3 |
| White | 40.8 | 40.0 |
| Other/NA | 11.2 | 5.7 |
| Resided within 2 miles of the WTC in the month after 9/11 (%)c | 34.7 | 19.0 |
| No. (%) of nondetectable cord adducts | 37 (37.8) | 45 (42.9) |
| Cord adducts (adducts/108 nucleotides) | 0.24 ± 0.10 | 0.23 ± 0.10 |
| Maternal exposure to ETS (% reporting at least one smoker in the home)c | 24.5 | 11.4 |
| Marital status (% married or living with a partner) | 78.6 | 77.1 |
| Material hardship (% reporting at least one unmet need such as going without or having inadequate food, housing, or clothing at some point in the past year) | 10.2 | 6.7 |
| Sex of newborns (% male) | 50.0 | 41.9 |
| Gestational duration (days) | 276.6 ± 9.4 | 276.73 ± 9.4 |
| Maternal intelligence (TONI) | 97.4 ± 14.8 | 93.0 ± 13.9 |
| 3-year MDI | 95.2 ± 11.9 | 94.4 ± 9.3d |
| 3-year PDIe | 98.1 ± 12.8 | 99.7 ± 13.3f |
NA, not available. Values are mean ± SD except where noted.
a
These 105 children had PAH–DNA adducts in cord blood but lacked MDI (n = 89) and/or demographic exposure data required for the analyses.
b
Income based on midpoint of each of 10 household income categories, ranging from < $10,000 to > $90,000.
c
p < 0.05, chi-square test.
d
Only 16 subjects in this group had 3-year MDI test results.
e
Four subjects were lacking PDI data, so n = 94.
f
Only 15 subjects in this group had 3-year PDI test results.