Table 4.
Two-stage model of CD and ODD using DSM-IV hierarchy: Model fit statistics, standardized variance components, and genetic and environmental correlations. All models are adjusted for age.
| Model | Parameters | Comparison to full model | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CD | ODD | Correlations | ||||||||||
| a2 | c2 | e2 | a2 | c2 | e2 | rA | rC | rE | Δχ2 | df | p | |
| 1. Full two-stage ACE | .28 (.06–.52) | .31 (.09–.50) | .41 (.35–.48) | .60 (.46–.76) | .29 (.13–.43) | .11 (.09–.14) | .52 (.18–1.00) | .28 (−.23–.76) | .03 (−.12–.18) | -- | -- | -- |
| 2. Two-stage AE Model | .61 (.55–.67) | -- | .39 (.33–.45) | .89 (.86–.91) | -- | .11 (.09–.14) | .40 (.31.48) | -- | .03 (−.11–.18) | 19.01 | 3 | <.001 |
| 3. Two-stage CE Model | -- | .54 (.47–.59) | .46 (.41–.52) | -- | .78 (.74–.81) | .22 (.19–.26) | -- | .41 (.32–.49) | .15 (.05–.26) | 106.5 | 3 | <.001 |
| 4. Two-stage Orth A (No A cov): Test of genetic distinctness | .24 (.02–.45) | .34 (.16–.53) | .42 (.35–.49) | .58 (.44–.73) | .31 (.16–.44) | .11 (.09–.14) | -- | .81 (.64–1.00) | .12 (−.02–.25) | 8.65 | 1 | .003 |
| 5. Two-stage Orth C (No C cov): Test of shared E distinctness | .32 (.11–.55) | .27 (.07–.45) | .41 (.35–.48) | .63 (.49–.78) | .26 (.11–.40) | .11 (.09–.15) | .67 (.46–1.00) | -- | .01 (−.14–.15) | 1.45 | 1 | .229 |
| 6. Two-stage Unidim A: Test of complete genetic overlap | .11 (.04–.26) | .45 (.30–.55) | .44 (.39–.51) | .59 (.46–.65) | .29 (.22–.43) | .12 (.09–.14) | 1.0 | .15 (−.30–.50) | .01 (−.15–.13) | 3.03 | 1 | .082 |
| 7. Two-stage Unidim C: Test of complete shared E overlap | .50 (.18–.66) | .11 (.06–.39) | .39 (.33–.36) | .62 (.33–.86) | .27 (.03–.42) | .11 (.09–.14) | .23 (−.03–.58) | 1.0 | .06 (−.10–.21) | 6.65 | 1 | .01 |
| 8. Two-stage Unidim A + Orth C:Test of complete genetic overlap but specific shared E effects | .15 (.09–.23) | .41 (.32–.48) | .44 (.38–.50) | .61 (.47–.77) | .27 (.12–.41) | .11 (.09–.14) | 1.0 | -- | −.02 (−.16–.30) | 3.644 | 2 | .162 |