Next, we examined the association between childhood trauma exposure, APOEε4, and the intercepts and slopes of EEGc. The intercept estimates individual variation in starting values, which may reflect variations in genetic risk and different types of exposures prior to the measurement period, as well as other trait differences. The slope reflects how change in EEGc occurs over time, on average. Given the known co-occurrence of different types of trauma exposures, the models allowed for simultaneous testing of associations between trauma exposure types and EEGc intercept and slope. The models also evaluated whether intercept and growth parameters in EEGc were associated with AUDsx and PTSDsx. The direct effect of APOEε4 on AUDsx and PTSDsx was also included in the models. Figure 1 displays a path diagram for the main effects model. Interactions between APOEε4 and childhood trauma variables were examined in separate interaction effects models.
