The Autism-Spectrum Quotient (AQ): Evidence from Asperger syndrome/high-functioning autism, males and females, scientists and mathematicians

Currently there are no brief, self-administered instruments for measuring t he degree to which an adult with normal intelligence has the traits associa ted with the autistic spectrum. In this paper, we report on a new instrumen t to assess this: the Autism-Spectrum Quotient (AQ). Individuals score in t he range 0-50. Four groups of subjects were assessed: Group 1: 58 adults wi th Asperger syndrome (AS) or high-functioning autism (HFA); Group 2: 174 ra ndomly selected controls. Group 3: 840 students in Cambridge University; an d Group 4: 16 winners of the UK Mathematics Olympiad. The adults with AS/HF A had a mean AQ score of 35.8 (SD = 6.5), significantly higher than Group 2 controls (M = 16.4, SD = 6.3). 80% of the adults with AS/HFA scored 32+, v ersus 2% of controls. Among the controls, men scored slightly but significa ntly higher than women. No women scored extremely highly (AQ score 34+) whe reas 4% of men did so. Twice as many men (40%) as women (21%) scored at int ermediate levels (AQ score 20+). Among the AS/HFA group, male and female sc ores did not differ significantly. The students in Cambridge University did not differ from the randomly selected control group, but scientists (inclu ding mathematicians) scored significantly higher than both humanities and s ocial sciences students, confirming an earlier study that autistic conditio ns are associated with scientific skills. Within the sciences, mathematicia ns scored highest. This was replicated in Group 4, the Mathematics Olympiad winners scoring significantly higher than the male Cambridge humanities st udents. 6% of the student sample scored 32+ on the AQ. On interview, 11 out of 11 of these met three or more DSM-IV criteria for AS/HFA, and all were studying sciences/mathematics, and 7 of the 11 met threshold on these crite ria. Test-retest and interrater reliability of the AQ was good. The AQ is t hus a valuable instrument for rapidly quantifying where any given individua l is situated on the continuum from autism to normality. Its potential for screening for autism spectrum conditions in adults of normal intelligence r emains to be fully explored.