TABLE 1.

Descriptive Statistics of Modeled Variables Measured at 2 Different Points in Early Childhood

VariableMean (SD) or %
Age “1” (n = 1278)Age “3” (n = 1345)
Perinatal variables
 Male50.9%49.9%
 Race/ethnicity
  Hispanic16.8%17.2%
  Black26.3%25.7%
  Non-Hispanic, nonblack56.9%57.1%
 Gestational age, wk38.6 (1.9)38.6 (2.0)
 Maternal alcohol use during pregnancy30.6%29.2%
 Maternal tobacco use during pregnancy23.3%22.6%
Variables measured in early childhood (at age “1” or age “3”)
 No. of children in household2.3 (1.1)2.5 (1.1)
 Two-parent household79.7%79.2%
 Emotional support score (normalized)6.1 (1.0)6.0 (1.0)
 Cognitive stimulation score (normalized)6.0 (1.0)5.8 (1.0)
 Television hours watched per day2.2 (2.9)3.6 (2.9)
Variables measured at index
 Child’s age, mo92.3 (6.8)92.4 (6.8)
 Mother’s age, y36.3 (2.6)36.3 (2.6)
 Urban/rural residence
  Non-MSA14.6%14.9%
  MSA-not central city52.1%53.3%
  MSA-central city unknown10.5%10.0%
  MSA-central city22.8%21.8%
 Index year
  199637.3%37.9%
  199839.7%40.4%
  200023.0%21.7%
 Maternal education, y13.3 (2.3)13.4 (2.3)
 Attentional problem10.4%9.6%
Additional variables
 Maternal CES-D, 199210.1 (9.3)9.8 (9.0)
 Maternal self-esteem, 19874.0 (1.0)4.0 (1.0)
  • MSA indicates Metropolitan Statistical Areas.