Question: What is the range of outcomes for children with autism who receive effective early intervention?
Answer: The range of outcomes varies widely. And unfortunately group data cannot tell you how any one child with autism will develop. Some children make substantial gains, are able to enter typical educational settings without additional help, and a few if any signs of autism in later years. Other children make substantial gains but still require support, whereas other children make gains but require a great deal of help.
There are many factors affecting the response to treatment and we haven't sorted them all out yet. We do know of a few. The first is age at onset of treatment. Children who enter early intervention programs at a younger age tend to do better. Secondly is the intensity of treatment. Children who are in more intensive programs of 25 hours a week or more tend to do better. Children who acquire vocal speech by age five and whose non-verbal cognitive abilities appear to be intact also tend to have better outcomes.