Objective: The prevalence of pervasive developmental disorders (PDD) is not well established and needs monitoring. The prevalence of PDD in the 1999 nationwide British survey of child and adolescent mental health was investigated.
Method: A randomized, stratified sample of children (N= 12,529) aged 5 to 15 years was generated from the Child Benefit Register. Trained interviewers interviewed parents and youths aged 11 or older with a standardized diagnostic interview (Development and Well-Being Assessment), and questionnaire data (Strengths and Difficulties Questionnaire) were obtained from teachers and parents, who also completed self-report measures of psychological distress. Final diagnostic determination was achieved by a team of experienced clinicians using all data sources.
Results: A total of 10,438 (83%) interviews were conducted. There were 2 girls with Rett syndrome (weighted prevalence: 3.8/10,000 girls) and 27 children with other PDD (weighted prevalence: 26.1/10,000). Compared with children with a psychiatric disorder other than PDD, social but not behavioral problems were more frequent in the PDD group. Parents of children with PDD had higher rates of psychological distress than those from the two comparison groups.
Conclusions: Consistent with other recent surveys, PDD rates are higher than those reported 30 years ago. The burden associated with PDD is very high.