Table 1.
| Characteristic | MZ (n = 159) | DZ (n = 98) | Twin 1 (n = 132) | Twin 2 (n = 131) |
|---|---|---|---|---|
| Mental well-being | 100.0 ± 10.2 | 99.5 ± 10.1 | 100.5 ± 9.9 | 99.3 ± 10.7 |
| Depression/anxiety symptoms | 10.4 ± 10.8 | 11.7 ± 10.7 | 10.4 ± 10.6 | 11.1 ± 10.7 |
| Early-life stress events | 1.7 ± 1.7 | 1.4 ± 1.4 | 1.6 ± 1.7 | 1.6 ± 1.6 |
| Premature birth or other birth complications | 47% | 44% | 45% | 47% |
| Adoption | 0% | 0% | 0% | 0% |
| Major surgery or repeated hospitalization | 11% | 15% | 12% | 14% |
| Life-threatening illness or injury | 10% | 8% | 11% | 8% |
| Sustained bullying | 17% | 15% | 13% | 20% |
| Physical abuse | 5% | 3% | 5% | 4% |
| Sexual abuse | 5% | 6% | 7% | 4% |
| Emotional abuse | 9% | 10% | 10% | 8% |
| Poverty or neglect | 2% | 0% | 1% | 2% |
| Natural disaster | 4% | 0% | 2% | 4% |
| House destroyed by fire or other means | 1% | 0% | 0% | 1% |
| Witness of warfare | 0% | 0% | 0% | 0% |
| Parents divorced or separated | 10% | 5% | 9% | 8% |
| Long period of separation from immediate family | 7% | 4% | 7% | 5% |
| Sustained family conflict | 12% | 13% | 14% | 11% |
| Death of immediate family | 3% | 3% | 4% | 3% |
| Life-threatening illness in immediate family | 6% | 7% | 8% | 7% |
| Witness domestic violence in family | 12% | 5% | 8% | 10% |
| Witness or experience some other traumatic event | 6% | 5% | 6% | 5% |
DZ = dizygotic; MZ = monozygotic.
*
Results presented as mean ± standard deviation, or as frequency (%).
†
No significant differences between groups for well-being, depression and anxiety scores, or average early-life events.