The Autism-Spectrum Quotient (AQ)—Adolescent Version Simon Baron-Cohen, 1,2 Rosa A. Hoekstra, 1 Rebecca Knickmeyer, 1 and Sally Wheelwright 1 The Autism Spectrum Quotient (AQ) quantifies autistic traits in adults. This paper adapted the AQ for children (age 9.8–15.4 years). Three groups of participants were assessed: Group 1: n=52 adolescents with Asperger Syndrome (AS) or high-functioning autism (HFA); Group 2: n=79 adolescents with classic autism; and Group 3, n=50 controls. The adolescents with AS/ HFA did not differ significantly from the adolescents with autism but both clinical groups scored higher than controls. Approximately 90% of the adolescents with AS/HFA and autism scored 30+, vs. none of the controls. Among the controls, boys scored higher than girls. The AQ can rapidly quantify where an adolescent is situated on the continuum from autism to normality. KEY WORDS: AQ; adolescents; screening; autistic spectrum; Asperger Syndrome. INTRODUCTION In an earlier issue in this journal, we reported on the Autism Spectrum Quotient (AQ) in adults with high functioning autism (HFA) or Asperger Syndrome (AS) (Baron-Cohen, Wheelwright, Skin- ner, Martin, & Clubley, 2001). The adult AQ was developed because of a lack of a quick and quan- titative self-report instrument for assessing how many autistic traits any adult has. The minimum score on the AQ is 0 and the maximum 50. If an adult has equal to or more than 32 out of 50 such traits, this is highly predictive of AS. The AQ has been found to correlate inversely with the Empathy Quotient (EQ) (Baron-Cohen & Wheelwright, 2004), the Friendship and Relationship Quotient (FQ) (Baron-Cohen & Wheelwright, 2003) and to corre- late positively with the Systemizing Quotient (SQ) (Baron-Cohen, Richler, Bisarya, Gurunathan, & Wheelwright, 2003). The AQ has also been found to be strongly predictive of who receives a diagnosis of AS in a clinic setting (Woodbury-Smith, Robinson, & Baron-Cohen, 2005). The AQ also reveals sex differences (males> females) and cognitive differences (scientists>non- scientists) (Baron-Cohen et al., 2001), a pattern of results that has been closely replicated in a Japanese sample (Wakabayashi, Baron-Cohen, & Wheelwright, 2004). This latter pattern suggests that these effects are not culture-specific and may instead reflect sexual dimorphism in the brain and differences in neural organization between scientists (a clear example of ‘systemizersÕ) and non-scientists. The AQ depends on self-report, which may be a concern in individuals whose social deficits may impair their accuracy in self-awareness. However, a parent-version confirms that adults of normal IQ with autism spectrum conditions are able to provide such information reliably (Baron-Cohen et al., 2001). Although the AQ is useful both clinically and in research studies as a screen for diagnosis, it has not been studied as a general population screen, and indeed if it was tested for this purpose it is likely that 1 Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK. 2 Correspondence should be addressed to: Simon Baron-Cohen, Department of Psychiatry, Autism Research Centre, University of Cambridge, Douglas House, 18b Trumpington Road, CB2 2AH, Cambridge, UK.; e-mail: sb205@cam.ac.uk Journal of Autism and Developmental Disorders, Vol. 36, No. 3, April 2006 (Ó 2006) DOI 10.1007/s10803-006-0073-6 Published Online: March 22, 2006 343 0162-3257/06/0400-0343/0 Ó 2006 Springer ScienceþBusiness Media, Inc.