Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by pervasive difficulties since early childhood across reciprocal social communication and restricted, repetitive interests and behaviors. Although early research in ASD focused primarily on children, there is increasing recognition that ASD is a lifelong neurodevelopmental disorder that has a potentially detrimental impact on adult functioning.
National Health Service (United Kingdom)
Autism spectrum disorder (ASD) is the name for a range of similar conditions, including Asperger syndrome, that affect a person’s social interaction, communication, interests and behaviour.
Centers for Disease Control – Diagnosing autism spectrum disorders
The American Psychiatric Association’s Diagnostic and Statistical Manual, Fifth Edition (DSM-5) provides standardized criteria to help diagnose ASD.