Table 1.
Sample characteristics—behavioral outcomes.
| Variables | Wave 1 (12 years) |
Wave 2 (16 years) |
Wave 3 (23 years) |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N | Mean | SD | Range | N | Mean | SD | Range | N | Mean | SD | Range | |
| Age (years) | 158 | 11.6 | 0.96 | 9.9–14.4 | 90 | 15.5 | 0.46 | 14.7–16.8 | 126 | 23.2 | 0.79 | 21.3–25.1 |
| Outcome variables | ||||||||||||
| Parent report | ||||||||||||
| SDQ ADHD | 146 | 7.6 | 2.4 | 0–10 | 84 | 5.9 | 2.5 | 0–10 | 121 | 5.1 | 2.6 | 0–10 |
| SDQ Conduct | 146 | 3.4 | 2.4 | 0–10 | 84 | 1.8 | 1.6 | 0–8 | 121 | 2.1 | 1.7 | 0–8 |
| SDQ Emotional | 146 | 4.6 | 2.7 | 0–10 | 84 | 3.5 | 2.4 | 0–9 | 121 | 3.9 | 2.4 | 0–9 |
| Teacher report | ||||||||||||
| SDQ ADHD | 133 | 4.1 | 1.6 | 0–8 | – | – | – | – | – | – | – | – |
| SDQ Conduct | 131 | 3.0 | 1.6 | 0–9 | – | – | – | – | – | – | – | – |
| SDQ Emotional | 132 | 3.5 | 2.5 | 0–10 | – | – | – | – | – | – | – | – |
| Recorded IQ | 156 | 72.2 | 24.5 | 19–136 | – | – | – | – | – | – | – | – |
SDQ: Strengths and Difficulties Questionnaire; ADHD: attention deficit hyperactivity disorder; IQ: intelligence quotient.