No Sex Differences in Cognitive Ability in Young Children with Autism Spectrum Disorder.
Boys and girls with ASD score the same on early Mullen tests, so use one norm set and focus on skill level, not sex.
01Research in Context
What this study did
The team looked at Mullen cognitive scores for 468 U.S. toddlers and preschoolers with ASD.
They compared boys and girls to see if sex changed early ability scores.
What they found
Boys and girls earned the same visual, language, and total cognitive scores.
No gap showed up on any MSEL scale, so separate boy/girl norms are not needed.
How this fits with other research
Reichow (2012) pooled five meta-analyses and showed EIBI lifts IQ in preschoolers with ASD.
English et al. (2020) now tells us those baseline scores are the same for both sexes, so you can use one set of norms when you pick kids for treatment.
de Jonge et al. (2025) used the same MSEL non-verbal index and found early mental age predicts adult daily-living-skill paths.
Together the three papers say: expect equal starting scores, but watch non-verbal mental age—it still forecasts long-term gain.
Why it matters
You can skip boy-versus-girl tables when you interpret MSEL results under age six.
Pick kids for early ABA using the same cognitive cut-off, then track non-verbal mental age to judge who may need heavier daily-skills focus later.
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02At a glance
03Original abstract
Inconsistent findings regarding sex differences in cognition have been found in people with autism spectrum disorder (ASD). This study evaluated sex differences in cognitive-developmental functioning in a large clinical sample of young children diagnosed with ASD. The sample included children 18-68 months of age who received the Mullen Scales of Early Learning (MSEL) through Autism Treatment Network (ATN) sites from 2007 to 2013 (N = 1587, 16.7% female). In this large clinically referred sample of young children with ASD in the United States, no significant differences were found between the sexes for the MSEL Early Learning Composite (ELC) standard score, domain T Scores or age equivalents. These findings persisted when examining different age ranges, cognitive levels and domain profiles.
Journal of autism and developmental disorders, 2020 · doi:10.1007/s10803-019-03933-1