Table 1.
PRISM sample characteristics overall and by infant sex
| Overall (n = 308) | Boys (n = 171) | Girls (n = 137) | P a | |
|---|---|---|---|---|
| Maternal age (years) | 28.9 ± 5.7 | 28.8 ± 5.6 | 29.0 ± 5.9 | 0.77 |
| Race/ethnicity | 0.73 | |||
| White, non-Hispanic | 39 (12.7) | 24 (14.0) | 15 (11.0) | |
| Black, Black-Hispanic | 165 (53.6) | 87 (50.9) | 78 (56.9) | |
| Hispanic, non-Black | 95 (30.8) | 55 (32.2) | 40 (29.2) | |
| Other | 9 (2.9) | 5 (2.9) | 4 (2.9) | |
| Less than high school education | 125 (40.5) | 66 (38.6) | 59 (43.1) | 0.43 |
| Smoke exposureb | 121 (39.3) | 67 (39.2) | 54 (39.4) | 0.96 |
| Infant age at assessment (months) | 6.5 ± 1.6 | 6.4 ± 1.5 | 6.5 ± 1.7 | 0.75 |
| Gestational week of urine collection | 31.1 ± 6.0 | 30.9 ± 6.1 | 31.2 ± 5.9 | 0.63 |
| Maternal urinary creatinine (mg/dL)c | 108.57 (90.45) | 107.56 (90.45) | 107.81 (90.45) | 0.46 |
| IBQ-R scales | ||||
| Global Negative Affectivity | 3.14 ± 0.68 | 3.11 ± 0.64 | 3.18 ± 0.72 | 0.34 |
| Fear | 2.79 ± 1.03 | 2.62 ± 0.96 | 2.99 ± 1.08 | 0.002 |
| Sadness | 3.16 ± 0.88 | 3.17 ± 0.85 | 3.16 ± 0.92 | 0.95 |
| Distress to Limitations | 3.68 ± 0.91 | 3.66 ± 0.92 | 3.69 ± 0.91 | 0.78 |
| Falling Reactivity | 5.07 ± 1.03 | 5.02 ± 1.00 | 5.12 ± 1.06 | 0.40 |
Values are mean ± standard deviation or n (%) unless otherwise noted.
aP values are from t-tests (continuous variables) or chi-square tests of homogeneity (categorical variables) examining differences in covariates and IBQ-R scores by sex unless otherwise noted.
bDefined as maternal cigarette, cigar, or pipe smoking during pregnancy or exposure to environmental tobacco smoke for 1 hour or more per week during pregnancy.
cSummary statistics are geometric mean (interquartile range), and P values are from Wilcoxon Rank Sum tests.
IBQ-R indicates Infant Behavior Questionnaire-Revised.