The population prevalence of child psychiatric disorders in Danish 8- to 9-year-old children.

The overall prevalence rates of general and specific child psychiatric disorders in Danish children are unknown. In this study, which aimed to estimate prevalence rates, a multi-method strategy using a two-step design was employed. The first step involved assessment with the Child Behaviour Checklist (CBCL). The second step consisted of assessment using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children; Present and Lifetime version (K-SADS-PL), The Children's Global Assessment Scale (C-GAS), The Wechsler Intelligence Scale for Children (WISCIII), The Autism Spectrum Disorder Screening Questionnaire (ASSQ), and a checklist containing the diagnostic criteria for Pervasive Developmental Disorders (PDD). Non-respondents were assessed through teachers using a modified brief version of the K-SADS-PL. A total of 751 children were targeted. The overall estimated prevalence rate of child psychopathology was 11.8 % [95% confidence interval (CI): 8.8, 14.8]. Attention Deficit/ Hyperactivity Disorder (ADHD) was found to be the most common specific child psychiatric disorder. There was no difference in prevalence rates between respondents and non-respondents. The estimated prevalence rates were broadly comparable to prevalence rates found in other epidemiological studies. The teacher-based interview proved to be a valid instrument for the assessment of non-respondents.