Table 1.
Wave 1 Characteristics of Overall Sample plus Comparisons between ADHD and Comparison Groups
| Variable | Overall Sample N = 193 M (SD) |
ADHD Group n = 114 M (SD) |
Comparison Group n = 79 M (SD) |
pa |
|---|---|---|---|---|
|
|
|
|||
| Demographic | ||||
| Age (years) | 9.5 (1.7) | 9.7 (1.7) | 9.4 (1.7) | ns |
| Total annual family incomeb | 6.6 (2.6) | 6.4 (2.7) | 6.9 (2.4) | ns |
| Maternal educationc | 4.8 (0.9) | 4.7 (0.9) | 4.9 (0.9) | ns |
| Caucasian (%) | 55.4 | 59.6 | 49.4 | ns |
| Public Assistance (%) | 13.5 | 14.9 | 11.4 | ns |
| Adopted or in foster care (%) | 14.5 | 21.1 | 5.1 | .001* |
| Single-parent household | 27.5 | 31.6 | 21.5 | .08 |
| Maltreated (%) | 14.0 | 16.7 | 10.1 | ns |
| Prenatal and Cognitive | ||||
| Low birth weight (<2500g) (%) | 8.3 | 10.0 | 8.0 | ns |
| WISC-III Full Scale IQ | 105.3 (14.1) | 100.5 (13.4) | 112.1 (12.1) | <.001* |
| Reading Disorderd (%) | 9.3 | 13.4 | 3.8 | .02* |
| Math Disordere (%) | 11.9 | 16.1 | 6.3 | .03* |
| ADHD-Related | ||||
| SNAP-IV Total Symptom Scoref (0–3) | 1.18 (0.86) | 1.81 (0.48) | 0.27 (0.20) | <.001* |
| Comorbidities | ||||
| DISC-IV ODD/CDg (%) | 42.0 | 65.8 | 7.6 | <.001* |
| DISC-IV Anxiety/Depressionh (%) | 14.0 | 24.6 | 2.5 | <.001* |
Note. WISC-III = Wechsler Intelligence Scale for Children-III; WIAT = Wechsler Individual Achievement Test; SNAP-IV = Swanson, Nolan, and Pelham rating scale (see Swanson, 1992); HI = Hyperactivity/Impulsivity; DISC-IV = Diagnostic Interview Schedule for Children, 4th edition; ns = not significant.
Significant at p < .05.
ADHD Group vs. Comparison Group. Significance: t-test for continuous variables; Pearson chi-square statistic for categorical variables.
For total annual family income, 1 ≤ $10,000; 9 ≥ $75,000.
For maternal education, 1 = less than 8th grade; 6 = advanced or professional degree.
Reading Disorder defined as standard score <85 on Basic Reading subtest of Wave 1-administered WIAT.
Math Disorder defined as standard score <85 on Math Reasoning subtest of Wave 1-administered WIAT.
SNAP-IV Total Symptom Score defined as composite of the averaged mother-rated ADHD items and the averaged teacher-rated ADHD items
Diagnosis of Oppositional Defiant Disorder and/or Conduct Disorder.
Diagnosis of Anxiety Disorder and/or Major Depressive Episode and/or Dysthymia.