Autism Spectrum Quotient (AQ)

Background / Development

Developed in 2001 by Simon Baron-Cohen and colleagues at the Autism Research Centre, University of Cambridge, the Autism Spectrum Quotient (AQ) was designed to quantify autistic traits in adults with average or above-average intelligence.

It provides a standardized measure of the extent to which an individual exhibits behaviours and preferences associated with the autism spectrum.

Purpose / Intended Use

The AQ is a screening and research tool, not a diagnostic instrument.

It helps clinicians and researchers identify individuals who may benefit from further evaluation for Autism Spectrum Disorder (ASD) and allows quantification of autistic traits in the general population.

It is most often used in clinical assessments, research studies, and occupational or educational screening contexts.

Psychometric Properties

The AQ has been widely validated and translated across multiple languages.

It demonstrates robust psychometric performance, including:

• Internal consistency: α ≈ 0.80–0.85
• Test–retest reliability: strong stability over time
• Construct validity: correlates with clinical diagnoses and related measures such as the ADOS and ADI-R
• Sensitivity/Specificity: typically around 0.77–0.85 depending on cutoff and population

The tool is recognized as one of the most reliable self-report measures of autistic traits in adults.

Structure and Content

The AQ consists of 50 self-report items, each rated on a 4-point Likert scale from Definitely agree to Definitely disagree.

Items are divided into five domains:

• Social skill
• Attention switching
• Attention to detail
• Communication
• Imagination

Approximately half the items are reverse-scored. The AQ is available in both full and short forms (AQ-10, AQ-28) for faster screening.

Scoring and Interpretation

Each item contributes one point toward the total score, depending on response direction (range 0–50).

• Higher scores reflect stronger expression of autistic traits.
• Common cutoffs:
  • ≥26–32: Elevated autistic traits, warranting further assessment
  • <26: Within typical range of variation

Scores are not diagnostic and must be interpreted in context with clinical interviews, developmental history, and other standardized assessments.

Clinical Application

The AQ is used as part of comprehensive adult autism evaluations, screening in research or workplace settings, and population-level studies of neurodiversity.

Its simplicity and accessibility make it well-suited for initial triage, referral decision-making, or baseline data collection before formal diagnostic procedures.

References / Sources

Baron-Cohen, S., Wheelwright, S., Skinner, R., Martin, J., & Clubley, E. (2001). The Autism-Spectrum Quotient (AQ): Evidence from Asperger syndrome/high-functioning autism, males and females, scientists and mathematicians. Journal of Autism and Developmental Disorders, 31(1), 5–17. https://doi.org/10.1023/A:1005653411471