Table 3 presents the fit statistics for the models of G-E interplay between EXT and each environmental variable. Each environmental variable exerted large moderation effects on EXT as evidenced by the highly significant likelihood ratio tests. Follow-up model trimming analyses showed that each environmental variable moderated the unique additive genetic and nonshared environment variance in EXT, with 3 variables also moderating the unique shared environmental variance. These moderating effects on the C component necessitated retaining it in the model despite the univariate estimate of C on EXT being zero. Academic achievement and engagement and both peer affiliation variables also moderated the common additive genetic variance with EXT (prosocial peers also moderated the common nonshared environmental variance). Because members of a twin pair should not differ on the life events that constitute our measure of independent stressful life events, no genetic effect is expected, so it is inappropriate to estimate the G-E correlation63. Therefore, for independent stressful life events, we only allowed for moderation on the unique variance in EXT. While not ideal, this approach allowed us to examine at least
