After decades of describing autism as a disorder of boys, scientists have only begun exploring how it affects girls and women in the past few years. For example, there is some consensus now that females may need a bigger genetic hit to develop autism and that the current diagnostic tests may miss many girls with the disorder.
Given all that, it comes as a surprise that two new studies, both by reputable research teams, report no detectable differences between boys and girls with autism.
The first, led by Catherine Lord, assessed various aspects of development in 234 boys and 54 girls diagnosed with autism. The study design, described 5 September in the Journal of Autism and Developmental Disorders, was rigorous ... The researchers expected — based on the literature — to find that girls with autism have better verbal skills, poorer nonverbal skills and fewer repetitive behaviors than boys with the disorder. But in fact, they found no significant difference in any of these aspects. (They did find that girls in the control group have better language skills than boys in that group, which is consistent with what’s known about early language development.)
The second study, published 13 September in the same journal by Connie Kasari and her colleagues, is both smaller and more specific. It compared play behavior in 40 girls with autism and 40 boys matched for autism severity, with an average age of 40 months.
There is some evidence that both typically developing girls and girls with autism have better play skills than boys do. But once again, Kasari and her colleagues didn’t find any significant differences in play type or complexity between the boys and girls in their sample.