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Autism spectrum disorder: Diagnosis

Marilyn Augustyn, MD
Section Editors
Marc C Patterson, MD, FRACP
Carolyn Bridgemohan, MD
Deputy Editor
Mary M Torchia, MD


Autism spectrum disorder (ASD) is a biologically based neurodevelopmental disorder characterized by impairments in two major domains: 1) deficits in social communication and social interaction and 2) restricted repetitive patterns of behavior, interests, and activities [1]. ASD encompasses disorders previously known as autistic disorder (classic autism, sometimes called early infantile autism, childhood autism, or Kanner's autism), childhood disintegrative disorder, pervasive developmental disorder-not otherwise specified, and Asperger disorder (also known as Asperger syndrome). (See 'Diagnostic criteria' below and "Asperger syndrome (a specific autism spectrum disorder): Clinical features and diagnosis in children and adolescents" and "Asperger syndrome (a specific autism spectrum disorder): Management and prognosis in children and adolescents".)

The diagnosis of ASD will be reviewed here. Surveillance and screening for ASD and the terminology, epidemiology, pathogenesis, clinical features, and management of ASD are discussed separately. (See "Autism spectrum disorder: Surveillance and screening in primary care" and "Autism spectrum disorder: Terminology, epidemiology, and pathogenesis" and "Autism spectrum disorder: Clinical features" and "Autism spectrum disorder in children and adolescents: Overview of management".)


Overview — Evaluation for ASD should include a comprehensive assessment, preferably by a team that has expertise in the diagnosis and management of ASD [2-7]. The evaluation should include a complete history, physical examination, neurologic examination, and direct assessment of the child's social, language, and cognitive development. Sufficient time should be set aside for standardized parent interviews regarding current concerns and behavioral history, as well as structured observation of social and communicative behavior and play. (See 'Diagnosis' below.)

The comprehensive evaluation has several objectives [5,8,9]:

Definitive diagnosis of ASD (see 'Diagnosis' below)

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Literature review current through: Nov 2017. | This topic last updated: Nov 21, 2016.
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