Table 1.
Percentages and Means (and SDs) of Study Variables in All Participants and as a Function of Prenatal Exposure (PAE) Status and Results From Independent-Sample t-Tests for Continuous Study Variables and χ2 Tests for Dichotomous Study Variables Comparing the 2 Groups
| Variable (possible range) | All participants (N = 12,308) | PAE group (n = 3,695) | Non-PAE group (n = 8,613) | Test statistic comparing PAE vs. non-PAE groups |
|---|---|---|---|---|
| PAE status (0 = exposure; 1 = nonexposure) | 30.0% | – | – | – |
| Maternal covariate | ||||
| Age | 28.16 (4.91) | 26.27 (5.12) | 28.97 (4.58) | t(12,289) = −28.88*** |
| Education (0–4) | 1.99 (1.28) | 2.55 (1.22) | 1.78 (1.23) | t(11,547) = 29.78*** |
| Alcohol and illicit drug use during pregnancy | 1.34 (1.17) | 1.37 (1.26) | 1.32 (1.13) | t(12,305) = 2.15* |
| Depression and anxiety during pregnancy (0–6) | 0.70 (1.32) | 1.01 (1.53) | 0.57 (1.20) | t(12,281) = 17.09*** |
| Depression and anxiety 1–5 years after delivery (0–8) | 0.80 (1.57) | 1.02 (1.72) | 0.72 (1.50) | t(11,363) = 9.04*** |
| Depression and anxiety status 6–11 years after delivery (0–6) | 0.64 (1.22) | 0.78 (1.31) | 0.60 (1.18) | t(9,215) = 6.11*** |
| History of drug addiction | 0.5% | 1.3% | 0.2% | χ2(1,11,594) = 61.50*** |
| History of alcoholism | 1.0% | 2.1% | 0.5% | χ2(1,11,594) = 64.27*** |
| History of severe depression | 9.0% | 15.9% | 6.4% | χ2(1,11,594) = 250.95*** |
| Mother’ partner covariate | ||||
| History of drug addiction | 1.2% | 2.6% | 0.8% | χ2(18,035) = 40.04*** |
| History of alcoholism | 2.9% | 6.2% | 1.8% | χ2(17,975) = 98.42*** |
| History of severe depression | 6.1% | 10.1% | 4.9% | χ2(17,974) = 69.83*** |
| Teacher covariate | ||||
| Depression and anxiety at children’s ages 8 and 11 (0–4) | 0.36 (0.70) | 0.38 (0.70) | 0.36 (0.69) | t(8,093) = 1.47 |
| Children covariate | ||||
| IQ | 104.43 (16.44) | 100.69 (16.03) | 105.40 (16.40) | t(6,667) = −9.52*** |
| Female gender (0 = male; 1 = female) | 51.8% | 53.5% | 50.8% | t(12,299) = 2.76** |
| Stressful events experienced at ages 2–6 (0–77) | 5.94 (3.49) | 5.99 (3.82) | 5.92 (3.37) | t(11,144) = 0.85 |
| Mental health outcome | ||||
| Peer (isolation) problem at age 4 (0–10): maternal rating | 1.52 (1.48) | 1.75 (1.53) | 1.45 (1.46) | t(8,849) = 8.26*** |
| Peer (isolation) problem at age 7 (0–10): maternal rating | 1.06 (1.42) | 1.31 (1.57) | 0.99 (1.37) | t(8,099) = 8.48*** |
| Peer (isolation) problem at age 8 (0–10): teacher rating | 1.19 (1.78) | 1.51 (1.95) | 1.07 (1.70) | t(5,557) = 8.43*** |
| Peer (isolation) problem at age 10 (0–10): maternal rating | 1.12 (1.51) | 1.34 (1.61) | 1.06 (1.48) | t(7,379) = 6.54*** |
| Peer (isolation) problem at age 11 (0–10): teacher rating | 1.21 (1.84) | 1.48 (2.01) | 1.10 (1.75) | t(6,410) = 7.61*** |
| Peer (isolation) problem at age 11 (0–10): maternal rating | 1.10 (1.55) | 1.28 (1.63) | 1.06 (1.52) | t(6,742) = 4.78*** |
| Hyperactivity symptoms at age 4 (0–10): maternal rating | 3.96 (2.32) | 4.40 (2.35) | 3.82 (2.30) | t(8,823) = 10.22*** |
| Hyperactivity symptoms at age 7 (0–10): maternal rating | 3.38 (2.37) | 3.84 (2.48) | 3.25 (2.32) | t(8,083) = 9.33*** |
| Hyperactivity symptoms at age 8 (0–10): teacher rating | 2.64 (2.69) | 3.38 (2.90) | 2.35 (2.54) | t(5,557) = 12.96*** |
| Hyperactivity symptoms at age 10 (0–10): maternal rating | 2.94 (2.26) | 3.30 (2.36) | 2.84 (2.22) | t(7,390) = 7.19*** |
| Hyperactivity symptoms at age 11 (0–10): teacher rating | 2.27 (2.65) | 2.96 (2.93) | 1.20 (2.47) | t(6,410) = 13.49*** |
| Hyperactivity symptoms at age 11 (0–10): maternal rating | 2.75 (2.22) | 3.16 (2.33) | 2.64 (2.17) | t(6,722) = 7.77*** |
| Conduct problems at age 4 (0–10): maternal rating | 1.95 (1.41) | 2.31 (1.52) | 1.84 (1.35) | t(8,899) = 13.63*** |
| Conduct problems at age 7 (0–10): maternal rating | 1.61 (1.47) | 1.94 (1.59) | 1.51 (1.41) | t(8,104) = 11.05*** |
| Conduct problems at age 8 (0–10): teacher rating | 0.75 (1.43) | 1.16 (1.79) | 0.59 (1.23) | t(5,555) = 13.65*** |
| Conduct problems at age 10 (0–10): maternal rating | 1.27 (1.42) | 1.57 (1.63) | 1.20 (1.35) | t(7,389) = 9.31*** |
| Conduct problems at age 11 (0–10): teacher rating | 0.83 (1.60) | 1.34 (2.05) | 0.63 (1.32) | t(6,406) = 16.52*** |
| Conduct problems at age 11 (0–10): maternal rating | 1.20 (1.42) | 1.53 (1.60) | 1.11 (1.36) | t(6,738) = 9.77*** |
| Emotional symptoms at age 4 (0–10): maternal rating | 1.45 (1.51) | 1.53 (1.58) | 1.42 (1.48) | t(8,903) = 3.05** |
| Emotional symptoms at age 7 (0–10): maternal rating | 1.51 (1.67) | 1.64 (1.78) | 1.47 (1.64) | t(8,099) = 3.89*** |
| Emotional symptoms at age 8 (0–10): teacher rating | 1.38 (1.94) | 1.63 (2.11) | 1.29 (1.87) | t(5,557) = 5.85*** |
| Emotional symptoms at age 10 (0–10): maternal rating | 1.50 (1.76) | 1.63 (1.88) | 1.47 (1.72) | t(7,375) = 3.25** |
| Emotional symptoms at age 11 (0–10): teacher rating | 1.29 (1.88) | 1.57 (2.08) | 1.17 (1.77) | t(6,409) = 7.70*** |
| Emotional symptoms at age 11 (0–10): maternal rating | 1.46 (1.73) | 1.63 (1.86) | 1.41 (1.69) | t(6,721) = 4.16*** |
| Prosocial behavior at age 4 (0–10): maternal rating | 7.05 (1.98) | 6.97 (1.96) | 7.07 (1.99) | t(8,874) = −2.07* |
| Prosocial behavior at age 7 (0–10): maternal rating | 8.17 (1.76) | 8.11 (1.72) | 8.19 (1.78) | t(8,103) = −1.71 |
| Prosocial behavior at age 8 (0–10): teacher rating | 7.69 (2.44) | 7.21 (2.54) | 7.88 (2.37) | t(5,553) = −9.15*** |
| Prosocial behavior at age 10 (0–10): maternal rating | 8.31 (1.67) | 8.27 (1.64) | 8.32 (1.68) | t(7,396) = −1.02 |
| Prosocial behavior at age 11 (0–10): teacher rating | 7.88 (2.38) | 7.52 (2.52) | 8.03 (2.31) | t(6,410) = −7.88*** |
| Prosocial behavior at age 11 (0–10): maternal rating | 8.33 (1.68) | 8.27 (1.70) | 8.35 (1.68) | t(6,744) = −1.60 |
| Stress reactivity: maternal rating | ||||
| Age 2 (1–48) | 3.19 (2.47) | 3.57 (2.75) | 3.07 (2.36) | t(6,018) = 6.78*** |
| Age 3 (1–48) | 3.87 (2.77) | 4.24 (3.04) | 3.76 (2.66) | t(8,293) = 6.81*** |
| Age 4 (1–48) | 3.04 (2.19) | 3.21 (2.39) | 2.98 (2.12) | t(7,768) = 4.09*** |
| Age 5 (1–52) | 2.98 (2.14) | 3.18 (2.28) | 2.91 (2.08) | t(6,787) = 4.62*** |
| Age 6 (1–52) | 2.59 (1.97) | 2.79 (2.08) | 2.51 (1.92) | t(5,661) = 4.75*** |
Note. *p < .05, **p< .01, ***p < .001.