ds's neuropsych w/ a large university believes a lot of kids are being misdiagnosed with autism. The autism rate keeps going up, not down.
There are many reasons for the autism rate going up, but that's a conversation for another time.
My point stands: if a diagnosis is made with an appropriate assessment (autism specific interview, ADOS-2 with a research reliable examiner, additional cognitive/language/etc testing, additional reports from school/outside sources other than the parent, etc), the likelihood of that diagnosis changing is slim. Of course, there are always outliers, but they're just that: outliers.
The issue is really in the lack of appropriate diagnostic techniques, e.g. therapists diagnosing on the basis of an hour with the child every other week, quick diagnoses at intake during a psych hold, etc. I've seen plenty of those, and they're an issue. But, that's not just specific to ASD. I also see bipolar, schizophrenia, and other weighty diagnoses are also handed out like candy. I once saw a three year old who had been previously diagnosed with bipolar. Bipolar!
On the other hand, many children of color and girls are heavily underdiagnosed with ASD. All too often, children of color are instead diagnosed with conduct disorder, intellectual disability, schizophrenia, personality disorders, etc, before finally receiving ASD.
