Table 1.
Characteristics of study samples from Children of the NLSY79
| Whole Cohort
|
White
|
African American
|
|||||
|---|---|---|---|---|---|---|---|
| (n = 3 395) | (n = 2 127) | (n = 1 268) | Sig. | ||||
| mean | (SD) | mean | (SD) | mean | (SD) | p value | |
| Child | |||||||
| BPI total standardized score | 105.2 | (15.0) | 104.2 | (14.8) | 107.0 | (15.1) | <0.0001 |
| Gender (female) | 49.3% | 48.2% | 51.0% | 0.1160 | |||
| Birth order (First-born) | 44.6% | 46.7% | 41.1% | 0.0014 | |||
| BMI z-score | 0.37 | (1.18) | 0.30 | (1.15) | 0.49 | (1.2) | <0.0001 |
| Birth weight (kg) | 3.46 | (0.47) | 3.54 | (0.46) | 3.32 | (0.44) | <0.0001 |
| Mother | |||||||
| Prepregnancy weight status | 0.0026 | ||||||
| Underweight | 7.2% | 7.2% | 7.2% | ||||
| Overweight | 17.0% | 15.5% | 19.3% | ||||
| Obese | 9.5% | 8.7% | 10.7% | ||||
| Contemporaneous weight status | |||||||
| Underweight | 3.0% | 3.4% | 2.1% | ||||
| Overweight | 26.8% | 25.0% | 29.9% | ||||
| Obese | 23.9% | 17.9% | 33.9% | ||||
| Smoking during pregnancy (Yes) | 31.1% | 32.9% | 28.4% | 0.0060 | |||
| Maternal education (year) | 13.5 | (2.2) | 13.7 | (2.3) | 13.1 | (2.0) | <0.0001 |
| AFQT score | 42.6 | (28.4) | 54.3 | (26.1) | 23.0 | (19.9) | <0.0001 |
| Age at childbirth (year) | 25.4 | (5.4) | 26.3 | (5.2) | 24.0 | (5.4) | <0.0001 |
| Family background | |||||||
| HOME-SF emotional support | 97.9 | (12.3) | 102.2 | (9.5) | 90.6 | (13.0) | <0.0001 |
| Per capita income (2008 US $1000) | 16.5 | (19.8) | 20.3 | (22.3) | 10.1 | (12.2) | <0.0001 |
The p values shown are from the results of comparisons between White and African American children using t tests, Mann-Whitney-Wilcoxon tests, and χ2 tests.