Symptoms of anxiety and depression are commonly comorbid and partially share a genetic etiology. Mean levels of anxiety and depression increase over the transition to adolescence, particularly in girls, suggesting a possible role of pubertal development in the activation of underlying genetic risks. The current study examined how genetic and…

The present study examined, within a longitudinal family-informed design and across middle childhood, the predictive associations between preference for solitude and social wariness, two forms of social withdrawal, and peer difficulties. Specifically, preference for solitude, rather than social wariness, was expected to predict peer victimization…

Longitudinal data from a large sample of twins participating in the Netherlands Twin Register (n = 42,827, age range 3-16) were analyzed to investigate the genetic and environmental contributions to childhood aggression. Genetic auto-regressive (simplex) models were used to assess whether the same genes are involved or whether new genes come into…

Early attachment has both protective and risk factors as regards later mental health. In Finland, insecure-avoidant-type attachment is overrepresented. Does this indicate a risk for emotional and behavioural problems at preschool age? In this study, we examined and compared the association between attachment and mental health in Finnish singletons…

Prior work has suggested that inter-parental conflict likely plays an etiological role in child behavior problems. However, family-level measurement of inter-parental conflict in most traditional child twin studies has made it difficult to tease apart the specific causal mechanisms underlying this association. The Children's Perception of…

Identification of gene x environment interactions (GxE) for attention-deficit hyperactivity disorder (ADHD) is a crucial component to understanding the mechanisms underpinning the disorder, as prior work indicates large genetic influences and numerous environmental risk factors. Building on prior research, children's appraisals of self-blame were…

While social impairment, difficulties with communication, and restricted repetitive behaviors are central features of Autism Spectrum Disorders, physical clumsiness is a commonly co-occurring feature. In a sample of 398 twin pairs (aged 8-17 years) from the Italian Twin Registry we investigated the nature of the co-variation between a psychometric…

Behaviors characteristic of autism and ADHD emerge in early childhood, yet research investigating their comorbidity has focused on older children. This study aimed to explore the nature of the relationship between autistic-like traits and ADHD behaviors in a community sample of 2-year-olds. Twins from the Boston University Twin Project (N = 312…

Introduction: Most behavior checklists for attention problems or attention deficit/hyperactivity disorder (ADHD) such as the Child Behavior Checklist (CBCL) have a narrow range of scores, focusing on the extent to which problems are present. It has been proposed that measuring attention on a continuum, from positive attention skills to attention…

Objective: To explore the contributions of genetic and environmental influences to individual variation and covariation of the Child Behavior Checklist (CBCL) DSM-oriented scales (DOS) originally proposed by Achenbach and associates in 2001. Method: A classic twin study of 398 twin pairs ages 8 to 17 years belonging to the population-based Italian…

Background: The purpose of this study was to determine a score on the Obsessive Compulsive Scale (OCS) from the Child Behavior Checklist (CBCL) to screen for obsessive compulsive disorder (OCD) in children and to rigorously test the specificity and sensitivity of a single cutpoint. Methods: A receiver operating characteristic (ROC) curve analysis…

Background: Twin studies of childhood behavior problems support the conclusion that individual differences in impulsivity, hyperactivity, and inattention are largely due to genetic influences. Non-genetic variation is due to environmental influences that are unique to the individual, and possibly to rater contrast effects. In the present…