Maybe it doesn't matter. All you can do is love your child. The books say autism is fully expressed in 5 out of every 10,000 people. They say approximately 15 out of every 10,000 people have multiple autistic traits, but these folks do not suffer from full-blown autism. The books tell me that the best thing you can do for an autistic child is to structure her life.
Structure is everything.
Autistic people hate disorder. They prefer to live a life as structured as the listings in TV Guide. Minute by minute structure. Scheduled like network news. With structure, anxiety can be reduced.