The literature consistently shows an association between pubertal maturation and internalizing problems in girls. The association for boys is less clear. The present study examines genetic and environmental influences on the association between pubertal maturation and internalizing problems for boys and girls in two primarily Caucasian adolescent…

Prevalence differences in depressive symptoms between the sexes typically emerge in adolescence, with symptoms more prevalent among girls. Some evidence suggests that variation in onset and progression of puberty might contribute to these differences. This study used a genetically informative, longitudinal (assessed at ages 12, 14, and 17) sample…

Despite the well-established association between adolescent sexual activity and delinquent behavior, little research has examined the potential importance of relationship contexts in moderating this association. The current study used longitudinal, behavioral genetic data on 519 same-sex twin pairs (48.6% female) divided into two age cohorts…

The relation between timing of first sex and later delinquency was examined using a genetically informed sample of 534 same-sex twin pairs from the National Longitudinal Study of Adolescent Health, who were assessed at three time points over a 7-year interval. Genetic and environmental differences between families were found to account for the…

This study investigated genetic and environmental influences on the associations between mother-child relationship quality (warmth and hostility) and adolescent conduct problems and cigarette use. Participants included 601 mothers and adolescent twin pairs (aged 12-17 years). Mothers and adolescents provided separate reports of mother-to-child…

Established normative data on the Pubertal Development Scale (PDS) (A. Petersen and others, 1988) of two population-based birth cohorts of Finnish twin boys and girls assessed at ages 11-12 and 14 years (complete data for 664 boys and 681 girls). Also reports longitudinal analyses of the associations between pubertal development and substance use.…