Background: DSM-IV specifies three ADHD subtypes; the combined, the hyperactive-impulsive and the inattentive. Little is known about the developmental relationships underlying these subtypes. The objective of this study was to describe the development of parent-reported hyperactivity-impulsivity and inattention symptoms from childhood to…

Background: Childhood externalizing and internalizing behaviors have been associated with injury risk in childhood and adolescence, but it is unknown whether this association continues to hold in adulthood. We examined whether externalizing and internalizing behaviors expressed in childhood predict injuries in childhood, adolescence, and…

Background: While there is considerable evidence of income gradients in child and adolescent behaviour problems, evidence relating to children and young people's emotional difficulties is more mixed. Older studies reported no income differentials, while recent reports suggest that adolescents from low-income families are more likely to experience…

Background: Theory of mind (ToM) allows the understanding and prediction of other people's behaviours based on their mental states (e.g. beliefs). It is important for healthy social relationships and thus may contribute towards children's involvement in bullying. The present study investigated whether children involved in bullying during early…

Background: This paper examines familiality and candidate gene associations of cognitive measures as potential endophenotypes in attention-deficit/hyperactivity disorder (ADHD). Methods: The sample consists of 540 participants, aged 6 to 18, who were diagnosed with ADHD from 251 families recruited for a larger genetic study of ADHD. All members of…

Background: Identifying how genetic risk interacts with experience to predict psychopathology is an important step toward understanding the etiology of mental health problems. Few studies have examined genetic risk by experience interaction (GxE) in the development of childhood psychopathology. Methods: We used both co-twin and parent mental…

Background: Inpatient treatment is a complex intervention for the most serious mental health disorders in child and adolescent psychiatry. This is the first large-scale study into its effectiveness and costs. Previous studies have been criticised for methodological weaknesses. Methods: A prospective cohort study, including economic evaluation,…