A community survey establishing the prevalence rate of autistic disorder in adults with learning disability

AIMS AND METHOD Most studies into autistic disorder have concentrated on children. This study aims to establish a prevalence rate of autistic disorders in an adult population with learning disabilities. Adults accessing learning disability services were diagnosed as having an autistic disorder by a two-stage process. The first stage was screening using the Pervasive Developmental Disorder – Mental Retardation Scale and then those identified by screening were diagnosed clinically. RESULTS An overall population rate of 7.7/10 000 for autistic disorder was obtained, which is a prevalence rate of 30% in those with learning disability. The prevalence rate was higher in intensive service settings. CLINICAL IMPLICATIONS Specific funding and interventions need to be targeted for the treatment of autistic disorders.