Autism is a group of developmental brain disorders, collectively called autism spectrum disorder
(ASD). The term “spectrum” refers to the wide range of symptoms, skills, and levels of impairment,
�or disability, that children with ASD can have. Some children are mildly impaired by their symptoms, but others are severely disabled.
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ASD is diagnosed according to guidelines listed in the Diagnostic and Statistical Manual of Mental
Disorders, Fourth Edition – Text Revision (DSM-IV-TR).1 The manual currently defines five disorders, sometimes called pervasive developmental disorders (PDDs), as ASD: