Although many children are not diagnosed before the age of 3 years, researchers are now able to diagnose autism in infants as young as 12 months old; some research suggests autism can be identified as young as 6 months old.
The cause of autism has been a topic of considerable debate for decades. However, today we understand that its cause is largely genetic, with possible environmental contributors or triggers for some children.
Prognosis for a child with autism today is very positive, especially if that child receives early intervention at the first signs. Federal regulations, ethical guidelines, and current practice in the field dictate that interventions be research-based. This means that treatments and strategies must be based on quality research that has been published in a peer-reviewed professional journal.
Evidence-based practices for children with autism have been subject to a great deal of review in recent years, yielding a comprehensive list of those practices considered to meet the requirements of quality research base. Those can be found here. Among them is Applied Behavior Analysis (ABA), as well as a number of other strategies. With early intervention, children with autism have opportunities for greater success in all areas of their lives.