TABLE 2.
Primary hypothesis test
| Model | Res. DF | RSS | DF | SS | R2 | P (LRT) | |
|---|---|---|---|---|---|---|---|
| Intercept only | 416 | 384.5 | |||||
| +Age | 414 | 119.8 | 2 | 264.61 | 0.6883 | 3.16 × 10−199 | |
| +Gender | 413 | 119.8 | 1 | 7.19 × 10−5 | 0.6883 | 0.9874 | |
| +Environment | 403 | 111.1 | 10 | 8.71 | 0.711 | 4.7 × 10−4 | |
| +Genetic background | 393 | 105.1 | 10 | 6.01 | 0.7266 | 0.0128 | 4.92 × 10−206 |
| +PRS main effects | 388 | 102.1 | 5 | 3.07 | 0.7346 | 0.0397 | |
| +PRS age interactions | 378 | 97.6 | 10 | 4.5 | 0.7463 | 0.0654 | 0.0147 |
| −Omitted PRS terms | 389 | 101.3 | −11 | −3.72 | 0.7366 | 0.2117 |
Adding the joint effects of the 5 PRS (+PRS main effects, +PRS age interactions) is a significant improvement to the explanatory power of the model when compared to the baseline model (intercept, +age covariates, +gender covariates, +environmental covariates, +genetic background covariates). Breaking down the terms into themed groups suggests all covariates except gender are important aspects of the baseline model and the main effects of the PRS are more predictive than their age interactions. Removing the terms not considered for post hoc analysis (−omitted PRS terms) did not significantly reduce the fit of the model.