Gender Bias in Autism Research on Young Adults: A Scoping Review

Despite growing awareness of autism across the lifespan, the transition to adulthood remains relatively neglected. Autistic young adults and young adults with many autistic traits (the broader autism phenotype) sometimes face numerous challenges. To clarify how gender imbalance manifests across study areas and populations, the present scoping review examined potential gender bias in autism research involving young adults. This review is the first to systematically chart gender and gender-minority representation across ASD and autistic-trait research in this population. We mapped gender representation across 602 studies over time and across subject areas, intellectual levels, and geographical regions: an angle not previously synthesized. The results illustrate the widespread, severe neglect of gender minorities. Female representation in autism research steadily increased over time. Still, almost half of the studies recruited fewer women than expected (male-to-female ratio 4:1), and 50 studies included only males. In contrast, autistic trait research showed a slight bias toward females. These findings highlight uneven progress toward gender inclusivity and underscore the need for more balanced sampling in future studies.