Table 3.
Within-trait, cross-sib correlations and cross-trait, cross-sib correlations
| MZs (570 Pairs) | DZs (592 Pairs) | Twin-Sibs (426 Trios) | |
|---|---|---|---|
| MDD | 0.32 | 0.09 | 0.29 |
| GAD | 0.21 | 0.21 | 0.11 |
| SAD | 0.39 | 0.14 | 0.18 |
| CD | 0.57 | 0.32 | 0.20 |
| ADHD | 0.35 | 0.16 | 0.12 |
| ODD | 0.38 | 0.14 | 0.06 |
| MDD-SAD | 0.25 | −0.01 | 0.08 |
| MDD-GAD | 0.21 | −0.04 | 0.09 |
| MDD-ADHD | 0.20 | 0.13 | 0.12 |
| MDD-CD | 0.19 | 0.05 | 0.11 |
| MDD-ODD | 0.20 | 0.17 | 0.07 |
| SAD-GAD | 0.16 | 0.13 | 0.08 |
| SAD-ADHD | 0.19 | 0.11 | 0.01 |
| SAD-CD | 0.14 | 0.06 | 0.04 |
| SAD-ODD | 0.23 | 0.04 | 0.04 |
| GAD-ADHD | 0.13 | 0.11 | 0.07 |
| GAD-CD | 0.10 | 0.07 | 0.03 |
| GAD-ODD | 0.13 | 0.09 | 0.07 |
| ADHD-CD | 0.26 | 0.15 | 0.09 |
| ADHD-ODD | 0.26 | 0.19 | 0.12 |
| CD-ODD | 0.27 | 0.14 | 0.04 |
Note. MZs = monozygotic twin pairs; DZs = dizygotic twin pairs; MDD = major depressive disorder; GAD = generalized anxiety disorder; SAD = separation anxiety disorder; CD = conduct disorder; ADHD = attention-deficit/hyperactivity disorder; ODD = oppositional defiant disorder.