More about Autism

Autism spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communication and behavioral challenges. CDC is committed to continuing to provide essential data on ASD, search for factors that put children at risk for ASD and possible causes, and develop resources that help identify children with ASD as early as possible.

Diagnosing autism spectrum disorder (ASD) can be difficult, since there is no medical test, like a blood test, to diagnose the disorders. Doctors look at the child’s behavior and development to make a diagnosis.

ASD can sometimes be detected at 18 months or younger. By age 2, a diagnosis by an experienced professional can be considered very reliable.[1] However, many children do not receive a final diagnosis until much older. This delay means that children with an ASD might not get the help they need.

Down there is pa web page that you can visit for more information: 

http://www.cdc.gov/ncbddd/autism/index.html

Also it would be interesting if you read this article about Screening and Diagnosis.

http://www.cdc.gov/ncbddd/autism/screening.html