Table 1. Analytic sample description (N = 1,965).

	Mean or proportion	Range
Child's age in monthsˆ	111.63	105-129
Child low birth weight (< 2,500 grams)	0.10	0-1
Child male	0.52	0-1
Child's puberty scoreˆ	1.46	1.0-3.2
Mother non-Hispanic white, native born	0.22	0-1
Mother non-Hispanic black, native born	0.52	0-1
Mother Hispanic, native born	0.23	0-1
Mother other race/ethnicity, native born	0.03	0-1
Father same race/ethnicity as mother	0.86	0-1
Mother foreign born	0.11	0-1
Mother's ageˆˆ	30.05	19-50
Mother has less than high school education	0.31	0-1
Mother has high school diploma or GED	0.31	0-1
Mother attended some college	0.27	0-1
Mother is a college graduate	0.11	0-1
Household incomeˆˆ	$38,045.22	$0-$688,444
Biological parents marriedˆˆ	0.32	0-1
Biological parents cohabitingˆˆ	0.12	0-1
Number of children in homeˆˆ	2.50	0-10
Hours of sleep – age 9ˆ	9.44	6-14
Hours of sleep – age 5ˆˆ	8.95	6-15
Child's self-rated internalizing behavior (SDQ)ˆ	9.25	0-24
PCG's rating of child's internalizing behavior (CBCL)ˆ	3.73	0-42
Child's self-rated externalizing behavior (SDQ)ˆ	5.53	0-18
PCG's rating of child's externalizing behavior (CBCL)ˆ	6.28	0-70
Child's self-rated physical healthˆ	4.10	1-5
PCG's rating of child's physical healthˆ	4.40	1-5

Note:

^ˆmeasured at age 9;

^ˆˆmeasured at age 5;

other characteristics measured at baseline.