Geographic prevalence

I realize that cultural & diagnostic capability aspects come into play but, is there any way to get a good picture of the prevalence of autism geographically? (Developing / developed / poorer countries?)

[Jason C Bourret, Ph.D., BCBA-D]

Unfortunately there's no way of getting any sort of a good estimate right now. Even within the United States alone, the increasing estimates of the prevalence of autism stem largely from increases in what is being reported from areas in which the amount of testing has increased the most dramatically. Until testing methods are more standardized and there are known proportions of populations being tested, it’s very difficult to produce meaningful estimates of the sort you are asking about.