Can the Five Factor Model of Personality Account for the Variability of Autism Symptom Expression? Multivariate Approaches to Behavioral Phenotyping in Adult Autism Spectrum Disorder.

Bouck et al. (2016) asked adults with autism and neurotypical adults to fill out two questionnaires. One measured the Big Five personality traits: openness, conscientiousness, extraversion, agreeableness, and neuroticism. The other measured autism symptoms.

The team then used statistics to see how much of the autism symptom differences the personality traits could explain.

Personality captured 70 percent of the spread in autism symptoms. Within the autism group, four clear sub-types showed up. All four were high in neuroticism, but each had its own mix of the other four traits.

In plain words, knowing someone’s personality profile tells you most of what you need to know about how autism looks in that adult.

Lundin et al. (2019) and Jia et al. (2019) also used short self-report scales (AQ-10, AQ-9, RBQ-2A-R, SQ-7) to map autism traits in adults. Their work shows these brief tools are reliable; C et al. go further by showing personality can replace or enhance them.

Allen et al. (2016) and Gomez et al. (2019) used factor analysis on teacher or parent scales for youth. C et al. apply the same math to adult personality, proving the same sub-typing idea works across age and informant.

Zadok et al. (2024) meta-analysis found tiny autonomic differences between autistic and neurotypical adults. C et al. find huge personality differences. The two studies seem to clash, but they measure different things: body signals versus self-described style. Both can be true—biology may stay steady while personality varies.

If you assess adults with ASD, adding a quick Big Five checklist can give you a richer picture than autism-only scales. You can spot the high-neuroticism subgroup early and tailor coping plans for anxiety before it derails therapy. It’s free, fast, and evidence-based.