S Deb1, K B Prasad. 1. University of Wales College of Medicine, Cardiff.
Abstract
BACKGROUND: It has been suggested recently that the prevalence of autistic disorder may be rising. No prevalence study specifically among learning disabled children exists and so this study was prompted. METHOD: 767 children with a learning disability who attended 16 different special schools in the Grampian region of north-east Scotland were studied for a diagnosis of autistic disorder according to the DSM-III-R criteria. The study was conducted in three stages. In the first screening stage, a questionnaire was completed for each child by their teachers. In the second stage, teachers completed another questionnaire based on DSM-III-R criteria for autistic disorder. A final diagnosis was made on the basis of examination and information gathered from the questionnaires. RESULTS: Questionnaires were completed for 634 (82.7%) children. 14.3% of children with a learning disability fulfilled the diagnostic criteria for autistic disorder. There was a male:female ratio of 3:1. This gave a 9 per 10,000 minimum prevalence of autistic disorder among all school-age children in the Grampian region. There was a higher prevalence of autistic disorder in the cities compared with rural areas. The prevalence did not change with age but increased with decreasing IQ. CONCLUSION: The results of the study support the view that there may be an increasing prevalence of reported cases of autistic disorder.
BACKGROUND: It has been suggested recently that the prevalence of autistic disorder may be rising. No prevalence study specifically among learning disabled children exists and so this study was prompted. METHOD: 767 children with a learning disability who attended 16 different special schools in the Grampian region of north-east Scotland were studied for a diagnosis of autistic disorder according to the DSM-III-R criteria. The study was conducted in three stages. In the first screening stage, a questionnaire was completed for each child by their teachers. In the second stage, teachers completed another questionnaire based on DSM-III-R criteria for autistic disorder. A final diagnosis was made on the basis of examination and information gathered from the questionnaires. RESULTS: Questionnaires were completed for 634 (82.7%) children. 14.3% of children with a learning disability fulfilled the diagnostic criteria for autistic disorder. There was a male:female ratio of 3:1. This gave a 9 per 10,000 minimum prevalence of autistic disorder among all school-age children in the Grampian region. There was a higher prevalence of autistic disorder in the cities compared with rural areas. The prevalence did not change with age but increased with decreasing IQ. CONCLUSION: The results of the study support the view that there may be an increasing prevalence of reported cases of autistic disorder.
Authors: P A Filipek; P J Accardo; G T Baranek; E H Cook; G Dawson; B Gordon; J S Gravel; C P Johnson; R J Kallen; S E Levy; N J Minshew; S Ozonoff; B M Prizant; I Rapin; S J Rogers; W L Stone; S Teplin; R F Tuchman; F R Volkmar Journal: J Autism Dev Disord Date: 1999-12