Autism spectrum
The median prevalence rate of autism spectrum disorders in Europe is 61.9 per 10,000 people, while the median prevalence estimated in the United States is 65.5 per 10,000. In western nations, children who show developmental problems are referred for evaluation by a pediatrician. Preliminary screening instruments include the Modified Checklist for Autism in Toddlers (M-CHAT), Social Communication Questionnaire (SCQ), and Autism Spectrum Screening Questionnaire (ASSQ). Autism spectrum evaluations are typically conducted by professionals who specialize in developmental disorders, such as psychologists, psychiatrists, or neurologists. Diagnostic instruments that assessing clinicians may use include the Autism Diagnostic Interview-Revised, Autism Diagnostic Observation Schedule, and Childhood Autism Rating Scale, as well as clinical judgment using criteria from the "Diagnostic and Statistical Manual".