Abstract
Aggression is a multidimensional behavior that could be caused by different biopsychosocial variables. The aim of this study was to explore whether temperament, cortisol and sex moderate the relation between fathers' parenting style and aggressive behavior in school-aged children, and whether this corresponds to differential susceptibility or diathesis-stress. Participants were 158 children (88 boys and 70 girls) aged 8 years. Aggressive behavior was measured using the Direct and Indirect Aggression Scale and fathers informed about their child's temperament and their own parenting style through the Children's Behavior Questionnaire and the Parenting Styles and Dimensions Questionnaire (respectively). Children's' baseline saliva cortisol levels were analyzed through an enzyme immunoassay technique. The results revealed that high cortisol levels moderated the relation between fathers' low levels of authoritative parenting and boys' aggression. Moreover, high negative emotionality moderated the relation between permissive paternal parenting and girls' aggressive behavior, with both these relations being consistent with the diathesis-stress theory.