A twin study of specific behavioral problems of socialization as viewed by parents

Our study focused on the etilogy of specific behavioral problems rather than on a global syndrome such as hyerpactivity. As a first step in studying specific behavioral problems, we revised the Conners (1970) Parent Symptom Rating questionnaire to improve its factor structure. Our revised instrument and the test-retest reliabilities of its 12 scales are described. A classical twin analysis comparing intraclass correlations for 54 pairs of identical twins and 33 pairs of same-sex fraternal twins indicated substantial genetic influence on behavioral problems in school-aged children.