We tested for differences in the prevalence of autism spectrum conditions (ASC) in school-aged children in three geographical regions in the Netherlands. Schools were asked to provide the number of children enrolled, the number having a clinical diagnosis of ASC and/or two control neurodevelopmental conditions. Prevalence was evaluated by negative…

The "extreme male brain" theory suggests females with Autism Spectrum Conditions are hyper-masculinized in certain aspects of behavior. We predicted that females with Gender Identity Disorder (who are masculinized) would have elevated Autism Spectrum Quotient (AQ) scores. AQ scores from five groups were compared: (1) n = 61 transmen…

Adolescent versions of the Empathy Quotient (EQ) and Systemizing Quotient (SQ) were developed and administered to n = 1,030 parents of typically developing adolescents, aged 12-16 years. Both measures showed good test-retest reliability and high internal consistency. Girls scored significantly higher on the EQ, and boys scored significantly higher…

The Autism Spectrum Quotient (AQ) has been used to define the "broader" (BAP), "medium" (MAP) and "narrow" autism phenotypes (NAP). We used a new Italian version of the AQ to test if difference on AQ scores and the distribution of BAP, MAP and NAP in autism parents (n = 245) versus control parents (n = 300) were…

This study reports on the development and validation of an abridged version of the 50-item Autism-Spectrum Quotient (AQ), a self-report measure of autistic traits. We aimed to reduce the number of items whilst retaining high validity and a meaningful factor structure. The item reduction procedure was performed on data from 1,263 Dutch students and…

Children's versions of the Empathy Quotient (EQ-C) and Systemizing Quotient (SQ-C) were developed and administered to n = 1,256 parents of typically developing children, aged 4-11 years. Both measures showed good test-retest reliability and high internal consistency. As predicted, girls scored significantly higher on the EQ-C, and boys scored…

We report a major revision of the CHecklist for Autism in Toddlers (CHAT). This "quantitative" CHAT (Q-CHAT) contains 25 items, scored on a 5 point scale (0-4). The Q-CHAT was completed by parents of n = 779 unselected toddlers (mean age 21 months) and n = 160 toddlers and preschoolers (mean age 44 months) with an Autism Spectrum…

The Autism Spectrum Quotient-Children's Version (AQ-Child) is a parent-report questionnaire that aims to quantify autistic traits in children 4-11 years old. The range of scores on the AQ-Child is 0-150. It was administered to children with an autism spectrum condition (ASC) (n = 540) and a general population sample (n = 1,225). Results showed a…

We report a study comparing the narrative abilities of 12 adults with high-functioning autism (HFA) or Asperger Syndrome (AS) versus 12 matched controls. The study focuses on the use of referential expressions (temporal expressions and anaphoric pronouns) during a story-telling task. The aim was to assess pragmatics skills in people with HFA/AS in…

In the current study, the child AQ was administered in Japan, to examine whether the UK results for reliability and validity generalize to a different culture. Assessment groups were: Group 1: n = 81 children with Asperger Syndrome (AS) or high-functioning autism (HFA); Group 2: n = 22 children diagnosed PDD-NOS with average IQ; and Group 3: n =…

This study tests the empathizing-systemizing (E-S) theory of sex differences and the extreme male brain (EMB) theory of autism. Three groups of participants took part: n = 48 people with autism spectrum, n = 137 general population controls, and n = 1,250 university student controls. Each participant completed the Empathy Quotient (EQ) and the…

The AQ (Autism-Spectrum Quotient) is a self-administered instrument for measuring the degree to which an adult with normal intelligence has the traits associated with the autistic spectrum. The AQ was administered in Japan to test whether the UK results would generalize to a very different culture. Three groups of subjects, adults with AS or HFA…

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…

People show a left visual field (LVF) bias for faces, i.e., involving the right hemisphere of the brain. Lesion and neuroimaging studies confirm the importance of the right-hemisphere and suggest separable neural pathways for processing facial identity vs. emotions. We investigated the hemispheric processing of faces in adults with and without…

At the present time there are a large number of adults who have "suspected" Asperger syndrome (AS). In this paper we describe a new instrument, the Adult Asperger Assessment (AAA), developed in our clinic for adults with AS. The need for a new instrument relevant to the diagnosis of AS in adulthood arises because existing instruments are designed…