Table 2.
Characteristics of Study Sample (n=3412)
| Characteristic | Mean | (SD) | Median | Range | n | (%) |
|---|---|---|---|---|---|---|
| Child | ||||||
| PIAT mathematics score | 99.9 | (13.6) | 101 | 65 – 135 | ||
| PIAT reading recognition score | 106.1 | (13.5) | 105 | 65 – 135 | ||
| Birth weight, kg | 3.42 | (0. 51) | 3.4 | 0.9 – 6.5 | ||
| Height z-score at testing | 0.24 | (1.3) | 0.3 | −6.4 – 6.4 | ||
| Height, cm | 116.1 | (7.6) | 116.8 | 88.9 – 152.4 | ||
| BMI z-score at testing | −0.06 | (1.5) | 0.09 | −5.9 – 3.4 | ||
| Age at testing, month | 71.5 | (6.7) | 72 | 60 – 83 | ||
| PPVT age at testing, month | 71.8 | (7.7) | 72 | 60 – 108 | ||
| Female | 1688 | (49.5) | ||||
| First born | 1416 | (41.5) | ||||
| Race/ethnicity | ||||||
| Hispanic | 697 | (20.4) | ||||
| African American | 1030 | (30.2) | ||||
| White | 1658 | (48.6) | ||||
| Asian | 27 | (0.8) | ||||
| Family Background | ||||||
| Average Home-SF score | 97.6 | (13.7) | 100 | 22 – 129 | ||
| Average per-capita income (in 2008 US $1000) | 15.8 | (20.5) | 11.2 | 0 – 293 | ||
| Mother | ||||||
| Education, year | 13.3 | (2.4) | 12 | 0 – 20 | ||
| AFQT percentile score | 39.4 | (27.9) | 35 | 0 – 100 | ||
| Age at child birth, year | 25.4 | (5.0) | 25 | 15 – 41 | ||
| Prepregnancy BMI (kg/m2) | ||||||
| BMI<18.5, underweight | 247 | (7.2) | ||||
| 18.5≤BMI<25, normal weight | 2239 | (65.6) | ||||
| 25≤ BMI<30, overweight | 599 | (17.6) | ||||
| 30≤ BMI, obese | 327 | (9.6) | ||||
| Gestational Weight Gain | ||||||
| below IOM recommendation | 843 | (24.7) | ||||
| within IOM recommendation | 1046 | (30.7) | ||||
| above IOM recommendation | 1523 | (44.6) | ||||
PIAT mathematics, reading recognition, HOME-SF scores are standardized to a mean of 100 and an SD of 15. Pregnancy weight gain categories were determined by amount of weight gain for each prepregnancy BMI category.