Robbers, S.C.C.

problem children externalizing problems divorce study internalizing externalizing singleton internalizing problems child behavior parent difference model family psychiatry sample effect level variance 12 years trajectorie childhood adhd symptoms age 3 verhulst factor child psychology growth development symptom chapter boomsma status rating journal result teacher class adolescent psychology divorce status attention attention problems age 12 score twin-singleton differences bartel research slope netherland adolescent psychiatry twin-singleton scale number influence intercept dutch interaction ages 3 mother assessment beijsterveldt heritability child behavior checklist university van der ende birth problem behaviors population table sibling report comparison modeling father analyses van den oord survey growth curves