Lots of you emailed me over the weekend, concerned that I didn’t understand there could be other reasons for the increase in “diagnosis” outside of an actual increase in prevalence. But you made me realize that I probably should have made some of those thoughts explicit. So here are some reasons that we could be seeing an increase in “diagnosis” outside of an actual doubling of the condition:
1) The definition of autism is evolving. It’s now a spectrum, and being identified in higher functioning individuals.
2) Awareness is increasing, leading more children to be labelled.
3) There are many areas where support for autism services are robust, but support for other disabilities are thin. Giving children the diagnosis of autism opens up doors for them that might otherwise be closed with respect to help.
4) Of course, the prevalence could be increasing as well.
There could be other reasons. My skepticism should not be taken as refusing to believe that autism is common or serious. Both these things are true. But we gain nothing by crying wolf, either, and we should be careful to throw around statistics that don’t seem realistic. If I’m wrong, and autism prevalence really is doubling every six years, I will shout it from the rooftops.