Table 3.
Number of children, n (%), with scores for ADHD and autistic traits above validated cut-offs
| ADHD | ASD | |||||||
|---|---|---|---|---|---|---|---|---|
| Cut-off | ≥6 | ≥12.5 | ≥4.5 | ≥8.5 | ||||
| Index twin | F** | M | F | M | F | M | F | M |
| Female co-twin | 137 (7.6) | 595 (14.2) | 17 (0.9) | 125 (3) | 40 (2.2) | 220 (5.2) | 10 (0.6) | 58 (1.4) |
| Male co-twin | 247 (5.9) | 274 (13) | 39 (0.9) | 52 (2.5) | 81 (1.9) | 103 (4.9) | 23 (0.5) | 25 (1.2) |
ADHD and autistic traits measured by the Autism—Tics, AD/HD, and other Comorbidities inventory (A-TAC)
F female index twin, M male index twin
**p = 0.01 for χ 2 analysis between female and male co-twins