Genetic and environmental influences on teacher ratings of the Child Behavior Checklist

The knowledge we have of childhood and adolescent behaviour is, to some ext ent, a function of the unique perspective of the rater. Although many behav ioural genetics studies have used parent and child self-reports in their as sessments of child and adolescent adjustment, few have included teacher rat ings of behaviour. It is possible that genetic and environmental contributi ons to teacher reports are different from those using parent and self-repor ts. The present study examined genetic and environmental influences on six subscales of the Child Behavior Checklist Teacher Report Form (CBC-TRF) usi ng a normative sample of adolescents. The sample consisted of 373 same-sex twin and sibling pairs of varying degrees of genetic relatedness participat ing in the Nonshared Environment in Adolescent project (NEAD). For all of t he CBC subscales, except attention problems and social problems, nonshared environmental influence was the most important source of variance. Additive genetic factors were of moderate importance for externalising behaviours, whereas nonadditive genetic factors contributed to the anxious/depressed, a ttention problems, withdrawn, and social problems subscales. For none of th e constructs was shared environment a significant influence. Three alternat ive models testing for contrast effects, differences in twin and nontwin si blings, and differences in nondivorced and stepfamilies were examined. In m ost cases, the best-fitting model was a model that did not include any of t hese effects, suggesting that these factors do not critically affect the ba sic model. However, some of the patterns of correlations and parameter esti mates were unusual and may warrant future investigation.