Mediation was tested using the multivariate delta method of calculating the standard error of the indirect effect (Sobel, 1982). The associated mediation z-scores are provided in Table 2, and the statistical significance of the mediation is based on bias-corrected bootstrap confidence intervals (MacKinnon et al., 2004). The 95% confidence intervals not including zero were interpreted as statistically significant. We found significant mediation of the family density effect on BD through demographic advantage (z=3.35) and through mother mental health (z=2.76). Mediation of the family density effect on CP was through demographic advantage (z=3.38), mother mental health (z=2.96), and mother deviance (z=2.65). The paths to and from father alcohol use were each statistically significant, but the mediation was marginally significant (z=1.78) and the 95% CI included zero. As a check on these findings that relied on missing data estimation, the model was run using only data from the 320 families in which two parents participated. The results [χ2(89)=155.48, p=.00, CFI=.97] were virtually identical to those found using the full sample.
