Multiple group structural equation modeling grouped by DRD4 genotype (7− vs. 7+) was applied to the model depicted in Figure 1. The path from adolescent perceived interparental positivity to threat was significant for 7+ adolescents (β = −.21, p < .05) but not for 7− adolescents (β = .06, ns). All other nonsignificant paths remained nonsignificant across genotypes and were set to zero (i.e., dropped). This trimmed model was then reestimated for the full sample (collapsed across genotypes) and revealed good fit to the data, χ2(5) = 5.54, ns; CFI = 1.00; TLI = 1.00; RMSEA = .02; SRMR = .02, suggesting that dropping these paths from the saturated model did not worsen model fit. Last, we reanalyzed the saturated multiple group model and constrained the paths that were dropped in the trimmed model to be equal across groups. The resulting model showed good fit to the data, χ2(5) = 3.32, ns; CFI = 1.00; TLI = 1.00; SRMR = .02, indicating these paths were not genetically moderated.
