Behavioural and cognitive sex/gender differences in autism spectrum condition and typically developing males and females.
Sex differences in core autism mirror typical kids, but linked traits like personality flip—so compare girls to both autistic and typical girls or you’ll miss them.
01Research in Context
What this study did
Fusar-Poli et al. (2017) hunted for every paper that compared boys and girls with autism to typical boys and girls. They looked at core traits like social trouble and repetitive play. They also checked linked traits like personality and thinking style.
The team pulled data from 62 studies. They asked one simple question: do sex differences in autism look like the usual boy-girl gaps we see everywhere else?
What they found
Core autism traits follow the same boy-girl pattern seen in typical kids. Boys still show more repetitive play. Girls still show more social interest, even when both groups have autism.
But linked traits flip the script. Typical girls outscore boys on Big Five traits like agreeableness. In autism, that gap shrinks or even reverses. The old rulebook does not hold.
How this fits with other research
Bassett-Gunter et al. (2017) looked only at kids with autism and found almost no sex gap. Laura’s team saw clear gaps because they added typical kids as a yard-stick. Same year, opposite headline—no true fight, just different lenses.
Krafft et al. (2019) later pooled 14 studies and confirmed the flip side: all Big Five traits drop in autism, but the drop is steepest for extraversion in girls. Laura’s pattern holds when numbers get crunched harder.
Hodge et al. (2025) checked real clinic files and found girls enter assessment six months later. Milder core signs fit Laura’s story: girls look “less autistic” on standard lists, so they wait.
Why it matters
Update your intake forms. If you only compare a girl to other autistic kids, you can miss her extra social spark and delay diagnosis. Stack her against same-age typical girls too. Watch for the quiet flip in personality traits—lower extraversion can hide in plain sight. Screen adaptive skills either way; Antoinette shows that’s where girls later struggle.
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02At a glance
03Original abstract
Studies assessing sex/gender differences in autism spectrum conditions often fail to include typically developing control groups. It is, therefore, unclear whether observed sex/gender differences reflect those found in the general population or are particular to autism spectrum conditions. A systematic search identified articles comparing behavioural and cognitive characteristics in males and females with and without an autism spectrum condition diagnosis. A total of 13 studies were included in meta-analyses of sex/gender differences in core autism spectrum condition symptoms (social/communication impairments and restricted/repetitive behaviours and interests) and intelligence quotient. A total of 20 studies were included in a qualitative review of sex/gender differences in additional autism spectrum condition symptoms. For core traits and intelligence quotient, sex/gender differences were comparable in autism spectrum conditions and typical samples. Some additional autism spectrum condition symptoms displayed different patterns of sex/gender differences in autism spectrum conditions and typically developing groups, including measures of executive function, empathising and systemising traits, internalising and externalising problems and play behaviours. Individuals with autism spectrum conditions display typical sex/gender differences in core autism spectrum condition traits, suggesting that diagnostic criteria based on these symptoms should take into account typical sex/gender differences. However, awareness of associated autism spectrum condition symptoms should include the possibility of different male and female phenotypes, to ensure those who do not fit the 'typical' autism spectrum condition presentation are not missed.
Autism : the international journal of research and practice, 2017 · doi:10.1177/1362361316669087