Table. Model-Fitting Results and Parameter Estimates of Obsessive-Compulsive Disorder Liability Heritability, Adjusted for Sex and Birth Yeara.
| Model | Model-fitting results | Parameter estimates, % (95% CI) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| −2 Log-likelihood statistic | df | Δχ2 (Δdf)b | P value | Akaike information criterion | Model compared with | A | C | E | |
| 1. Saturated | 8678.428 | 132 385 | NA | NA | 8696.428 | NA | NA | NA | NA |
| 2. ACE | 8679.764 | 132 388 | 1.336 (3) | .72 | 8693.764 | 1 | 59.9 (24.4 to 95.8) | −8.6 (−39.2 to 20.0) | 48.7 (38.1 to 60.8) |
| 3. AEc | 8680.094 | 132 389 | 0.330 (1) | .56 | 8692.094 | 2 | 50 (38.8 to 60.1) | NA | 50 (40.0 to 61.3) |
| 4. CE | 8690.732 | 132 389 | 10.968 (1) | <.001 | 8702.732 | 2 | NA | 35.9 (26.9 to 44.3) | 64.1 (55.7 to 73.1) |
| 5. E | 8743.899 | 132 390 | 64.135 (2) | <.001 | 8753.899 | 2 | NA | NA | 100 (100 to 100) |
Abbreviations: A, additive genetic; C, shared environmental; E, nonshared environmental; NA, not applicable.
a
Variance components are not constrained to be positive in the presented models.
b
The difference in −2 log-likelihood statistic and df between the submodel and the full model.
c
AE was the best-fitting model.