In the present study, we examined the association between maltreatment and children’s conduct problems by conducting a bivariate behavior genetic analysis. This extends the literature by using a composite measure of maltreatment rather than corporal punishment only, by assessing maltreatment occurring at a later age than a previous study (Jaffee et al. 2004b), and by using methods that have been demonstrated to be valid. The meaning of each model parameter is summarized in Table 1. Common genetic influences would indicate a nonpassive gene-environment correlation, or parents responding to children’s genetically-influenced conduct problems by maltreating them (i.e., genetic mediation). Common shared- and twin-environmental influences could reflect either passive gene-environment correlation or true environmental mediation. Common nonshared environmental influences would reflect common environmental influences that lead siblings to experience dissimilar levels of maltreatment and dissimilar levels of conduct problems (i.e., environmental mediation) or correlated measurement error. Significant common nonshared environmental influences would be consistent with the hypothesis that maltreatment causes conduct problems (although they would not be a proof of this hypothesis).
