Childhood risk factors |
Low birth weight |
17.59 % |
15.04 % |
0.547 |
12.82 % |
11.82 % |
0.793 |
Maternal age (range, 13–46 years), mean |
25.41 |
25.31 |
0.880 |
25.39 |
25.14 |
0.737 |
Parental death |
12.37 % |
7.49 % |
0.174 |
11.92 % |
10.98 % |
0.800 |
Maternal education (range, 0–22), mean |
10.20 |
10.76 |
0.030 |
10.58 |
10.55 |
0.916 |
Number of children in the household |
4.28 |
4.44 |
0.532 |
4.30 |
4.50 |
0.474 |
Intelligence quotient (IQ) (range, 67–129), mean |
96.34 |
96.37 |
0.973 |
94.62 |
94.33 |
0.859 |
Lower school expectations (range, 1–5), mean |
2.14 |
2.44 |
0.004 |
2.18 |
2.30 |
0.280 |
Mother Symptom Inventory (MSI) (range, 0–43), mean |
10.12 |
9.94 |
0.821 |
9.58 |
9.18 |
0.644 |
First-grade aggressive behavior (range, 0–3), mean |
0.35 |
0.59 |
0.010 |
0.69 |
0.75 |
0.621 |
First-grade underachievement (range, 0–3), mean |
0.57 |
0.66 |
0.421 |
0.80 |
0.75 |
0.648 |
First-grade shy behavior (range, 0–3), mean |
0.37 |
0.51 |
0.108 |
0.57 |
0.61 |
0.749 |
Family history and contextual risk factors across childhood and adolescence |
Maternal history of psychological distress |
None |
48.88 % |
46.96 % |
Ref |
45.32 % |
48.96 % |
Ref |
Childhood or adolescence only |
39.76 % |
32.75 % |
0.582 |
39.03 % |
35.46 % |
0.549 |
Persistent |
11.36 % |
20.29 % |
0.072 |
15.65 % |
15.58 % |
0.810 |
Poverty status |
Not poor |
36.81 % |
28.93 % |
Ref |
33.11 % |
20.96 % |
Ref |
Childhood or adolescence only |
32.51 % |
30.58 % |
0.548 |
34.77 % |
36.12 % |
0.171 |
Persistent poverty |
30.69 % |
40.49 % |
0.062 |
32.13 % |
42.92 % |
0.028 |
Female-headed household |
Neither |
50.09 % |
41.73 % |
Ref |
46.30 % |
37.61 % |
Ref |
Either childhood and adolescence |
32.72 % |
31.37 % |
0.611 |
34.21 % |
33.94 % |
0.518 |
Both childhood and adolescence |
17.18 % |
26.90 % |
0.042 |
19.49 % |
28.45 % |
0.069 |
Adolescent risk factors |
Reading test score (24–137), mean |
85.89 |
86.19 |
0.875 |
82.66 |
80.23 |
0.179 |
Physical health (range, 1–4), mean |
1.30 |
1.32 |
0.735 |
1.32 |
1.26 |
0.492 |
Higher family communication (range, 1–6), mean |
3.92 |
4.30 |
0.106 |
3.73 |
3.95 |
0.360 |
Family conflict (range, 1–6), mean |
3.71 |
4.46 |
<0.001 |
3.41 |
4.05 |
0.002 |
Low parental supervision |
15.77 % |
18.77 % |
0.606 |
24.12 % |
38.14 % |
0.027 |
Age of onset of marijuana use |
No use by age 16 years |
48.33 % |
41.52 % |
Ref |
34.05 % |
22.70 % |
Ref |
Ages 13–16 years |
48.63 % |
50.69 % |
0.488 |
56.90 % |
61.60 % |
0.165 |
Age 12 years or younger |
3.04 % |
7.78 % |
0.107 |
9.04 % |
15.71 % |
0.072 |
Delinquent behavior (range, 0–69), mean |
9.59 |
13.10 |
0.006 |
15.32 |
19.02 |
0.022 |
Depressed mood (range, 7–42), mean |
13.84 |
15.42 |
0.075 |
13.39 |
14.68 |
0.166 |
Anxious mood (range, 7–42), mean |
19.48 |
20.72 |
0.207 |
17.74 |
18.68 |
0.383 |