The risk of having at least 1 psychiatric disorder by age 16 years is much higher than point estimates would suggest. Concurrent comorbidity and homotypic and heterotypic continuity are more marked in girls than in boys.

No abstract

We review recent research on the prevalence, causes, and effects of diagnostic comorbidity among the most common groups of child and adolescent psychiatric disorders; anxiety disorders, depressive disorders, attention deficit hyperactivity disorders, oppositional defiant and conduct disorders, and substance abuse. A meta-analysis of representative general population studies provides estimates of the strength of associations between pairs of disorders with narrower confidence intervals than have previously been available. Current evidence convincingly eliminates methodological factors as a major cause of comorbidity. We review the implications of comorbidity for understanding the development of psychopathology and for nosology.

In the general population of children, potentially traumatic events are fairly common and do not often result in PTS symptoms, except after multiple traumas or a history of anxiety. The prognosis after the first lifetime trauma exposure was generally favorable. Apart from PTSD, traumatic events are related to many forms of psychopathology, with the strongest links being with anxiety and depressive disorders.