Table 1.
Demographic characteristics of the 90 youth participating in the present study
| Percentage, n, or M (SD) | |
|---|---|
| Gender (boys/girls) | |
| Boys | 64.4 |
| Girls | 35.6 |
| Age (months) | 129.59 (30.21) |
| 6–12 years | 71.1 |
| 13–16 years | 28.9 |
| Intelligence (IQ)a | 103.13 (15.75) |
| Education | |
| Regular primary school | 65.5 |
| Special primary school | 3.3 |
| Lower vocational education | 8.9 |
| Higher general secondary education | 7.8 |
| Pre-university education | 2.2 |
| Special secondary school | 1.1 |
| International school | 1.1 |
| Nationality of parents | |
| Dutch | 77.8 |
| Other | 22.2 |
| Family structure | |
| Complete | 65.4 |
| Broken | 34.6 |
| Socio-economic status | |
| Low | 45.7 |
| Medium | 38.3 |
| High | 16.0 |
| ADHD diagnosis | |
| ADHD combined type | 55.4 |
| ADHD predominantly inattentive type | 44.5 |
| ADHD-NOS | 1.1 |
| Level of interference (ADIS) | 1.1 |
| Comorbidity | |
| Yes | 61.7 |
| No | 38.3 |
| Comorbid disordersb | |
| Parent–child relational problem | 25 |
| Pervasive developmental disorder | 9 |
| Relational problem related to a mental disorder | 9 |
| Dyslexia | 7 |
| ODD/disruptive behavior disorder NOS | 7 |
| Anxiety/mood disorder | 6 |
| Identity problem | 5 |
| Reactive attachment disorder | 2 |
| Sibling relational problem | 2 |
| Partner relational problem | 1 |
| Adjustment disorder | 1 |
| Enuresis | 1 |
ADIS anxiety disorder interview schedule, ADHD section
aOnly available for 55 participants
bSome youth had more than one comorbid diagnosis