TABLE I.
Sample Characteristics
| Child 1
|
Child 2
|
|||||
|---|---|---|---|---|---|---|
| N | Mean | (SD) | N | Mean | (SD) | |
| Study variables | ||||||
| SDP severity | 173 | 3.95 | 2.05 | 167 | 2.04 | 1.77 |
| Conners-parent inattention (IN) | 165 | 3.90 | 3.56 | 162 | 4.59 | 3.89 |
| Conners-parent hyperactive (HI) | 165 | 2.55 | 3.03 | 162 | 4.30 | 4.20 |
| Conners-parent total ADHD | 165 | 6.45 | 5.87 | 162 | 8.89 | 7.45 |
| CBCL total ADHD | 164 | 2.91 | 2.79 | 161 | 3.78 | 3.62 |
| Conners-teacher inattention (IN) | 110 | 3.46 | 2.90 | 113 | 4.70 | 3.33 |
| Conners-teacher hyperactive (HI) | 110 | 2.05 | 3.09 | 113 | 3.74 | 4.13 |
| Conners-teacher total ADHD | 110 | 5.51 | 5.43 | 113 | 8.44 | 6.71 |
| TRF total ADHD | 110 | 5.86 | 5.93 | 109 | 5.03 | 4.85 |
| Conners-composite inattention (IN) | 167 | 6.13 | 4.93 | 166 | 7.83 | 5.54 |
| Conners-composite hyperactive (HI) | 167 | 3.58 | 4.05 | 166 | 6.18 | 5.22 |
| Conners-composite total ADHD | 167 | 9.71 | 8.13 | 166 | 14.01 | 9.79 |
| CBCL/TRF composite total ADHD | 164 | 7.25 | 5.39 | 162 | 7.83 | 5.42 |
| Covariates | ||||||
| Maternal age at birth | 143 | 26.64 | 5.40 | 145 | 29.48 | 5.60 |
| Maternal education (in years) at birth | 143 | 13.31 | 2.10 | 145 | 13.59 | 1.90 |
| Second-hand smoke exposure by fathers | 171 | 1.84 | 1.44 | 159 | 1.13 | 1.42 |
| N | % | N | % | |||
| Marital status (percent married) at birth | 143 | 85 | 145 | 85 | ||
| Food stamp usage at birth | 142 | 7 | 142 | 11 | ||
|
| ||||||
| Family demographics (at assessment) | N | Mean | (SD) | |||
| Maternal age | 162 | 39.83 | 5.62 | |||
| Paternal age | 80 | 44.04 | 6.34 | |||
| Child 1 age | 173 | 12.99 | 1.95 | |||
| Child 2 age | 170 | 10.19 | 1.80 | |||
| Child age difference | 170 | 2.79 | 1.54 | |||
| N | % | |||||
| Maternal education | ||||||
| Less than HS | 7 | 4 | ||||
| HS | 30 | 18 | ||||
| 1–2 years college | 50 | 30 | ||||
| 3–4 years college | 46 | 27 | ||||
| More than college | 29 | 17 | ||||
| Not reported | 7 | 4 | ||||
| Paternal education | ||||||
| Less than HS | 9 | 10 | ||||
| HS | 19 | 20 | ||||
| 1–2 years college | 14 | 15 | ||||
| 3–4 years college | 17 | 18 | ||||
| More than college | 21 | 22 | ||||
| Not reported | 14 | 15 | ||||
| Mothers’ marital status | ||||||
| Never married | 6 | 4 | ||||
| Married | 130 | 77 | ||||
| Separated | 5 | 3 | ||||
| Divorced | 26 | 15 | ||||
| Widowed | 2 | 1 | ||||
SDP, smoking during pregnancy; ADHD, attention deficit/hyperactivity disorder symptoms; CBCL, child behavior checklist; TRF, teacher report form; HS, high school.
*
All ADHD variables are presented in this table as raw and unstandardized data for descriptive purposes; however, for analyses, they are log-transformed and standardized.