Autism spectrum, also known as autism spectrum disorder (ASD), is a range of neurodevelopmental disorders. It included autism and Asperger syndrome and other neurodevelopmental disorders until 2013 when all disorders under ASD were reclassified as ASD instead of as individual disorders. Individuals on the autistic spectrum experience difficulties with social communication and interaction and also exhibit restricted, repetitive patterns of behavior, interests, or activities. Symptoms are typically recognized between one and two years of age. Long-term problems may include difficulties in performing daily tasks, creating and keeping relationships, and maintaining a job.

The cause of autism spectrum is uncertain. Risk factors include having an older parent, a family history of autism, and certain genetic conditions. It is estimated that between 64% and 91% of risk is due to family history. Diagnosis is based on symptoms. In 2013, the Statistical Manual of Mental Disorders version 5 (DSM-5) replaced the previous subgroups of autistic disorder, Asperger syndrome, pervasive developmental disorder not otherwise specified (PDD-NOS), and childhood disintegrative disorder with the single term “autism spectrum disorder”.

Treatment efforts are generally individualized and can include behavioural therapy and the teaching of coping skills. Medications may be used to try to help improve symptoms. Evidence to support the use of medications, however, is not very strong.

Autism spectrum is estimated to affect about 1% of people (62.2 million globally) as of 2015. In the United States it is estimated to affect more than 2% of children (about 1.5 million) as of 2016. Males are diagnosed four times more often than females. The term “spectrum” refers to the variation in the type and severity of symptoms. Those in the mild range may function independently, while those with moderate to severe symptoms may require substantial support in their daily lives.