Evaluating Sex Differences in Language Abilities Within Down Syndrome and Autism Spectrum Disorder.

Parents filled out a language survey about their kids. The sample included children with Down syndrome, autism, and typical development. Researchers then looked for sex differences in the parent ratings.

Girls with Down syndrome scored higher on parent-reported language than boys with Down syndrome. In the autism and typical groups, boys and girls looked the same.

Kocher et al. (2015) and Matheis et al. (2019) also found no sex gap in toddlers with autism. Those studies looked at younger kids and matched IQ scores, which may hide small language differences.

Conlon et al. (2019) and Kauschke et al. (2016) show a different picture. When they asked school-age girls with autism to tell stories, the girls used richer language than boys. Parent surveys may miss these fine details.

Oates et al. (2023) scoping review ties it together. Autistic girls often outscore autistic boys on structural language, but both groups lag behind typical girls. The new survey data line up with that big-picture view.

If you test a girl with Down syndrome, expect her language to look stronger than a boy of the same age. In autism, sex differences are smaller and may only pop up on detailed tasks like storytelling. Use narrative probes, not just parent forms, to spot them.