More is involved than the needless emotional stresses of the parents. Many of the treatments inflicted on children diagnosed as autistic would be called child abuse if they were not done as medical procedures, and they can set back or distort a child's development.

Once the "autistic" label has been put on a child, it can follow him and her into schools and beyond, causing that child to be treated differently by teachers, nurses and others.

Too many people refuse to reconsider any evidence contrary to the label, however blatant that evidence becomes or however much that evidence increases over the years.

The initial evidence on which a diagnosis of autism was based may be nothing more than a checklist of characteristics of autistic children, often administered by someone with nothing more to go on than that checklist.

The fundamental problem is that many items on such a checklist can apply to many children who are not autistic. A study of gifted children, for example, found many of them showing the kinds of characteristics found on checklists for autism.

According to Professor Camarata, "because there are no reliable biomedical markers for autism, diagnosis must rely on subjective rating scales making it difficult if not impossible to conduct accurate screening in toddlers or preschoolers."

But it is precisely the checklist approach that is being urged by those who are crusading for every child to be diagnosed for autism before age two.

Like most crusaders, they seem unwilling to consider the possibility of errors, much less the consequences of those errors.

The very definition of autism has been expanded in recent years to include what is called "the autism spectrum." What this means, among other things, is that there is now far more wiggle room for those whose diagnoses have proved to be wrong, who refuse to admit it, and who are now even more unaccountable than ever.