What standardized tools or questionnaires are recommended for the screening and diagnosis of ASD in primary care?

Recommended standardized tools for screening and diagnosis of autism spectrum disorder (ASD) in primary care:

• For adults without moderate or severe learning disability, the Autism-Spectrum Quotient 10-item questionnaire (AQ-10, British version) is recommended as a brief screening tool suitable for primary care, social care, and other non-specialist settings. It takes about 2 minutes to administer and requires no special expertise. A score of 6 or above suggests the need for referral for a specialist assessment for ASD ¹,³.
• For adults with moderate or severe learning disabilities, no standardized self-completion tools are recommended. Instead, a brief clinician-led assessment focusing on key behavioural indicators (such as difficulties in reciprocal social interaction, lack of responsiveness, rigid routines, and stereotypic behaviours) is advised to decide on referral ¹,³.
• For children and young people, no single standardized diagnostic tool is recommended to be used alone. Instead, autism-specific tools may be used to gather developmental history and assess social and communication skills as part of a comprehensive diagnostic assessment based on ICD-11 or DSM-5 criteria. The assessment should include detailed history, observation, and information from multiple sources (parents, carers, schools) ²,⁴.
• Examples of comprehensive diagnostic tools used in specialist settings (not primary care) include the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and the Autism Diagnostic Interview-Revised (ADI-R), but these are not recommended for routine primary care screening ¹.

Summary: In primary care, the AQ-10 questionnaire is the recommended standardized screening tool for adults without learning disabilities. For children and adults with learning disabilities, clinical judgement supported by behavioural assessments and multi-source information is used to decide on referral for specialist diagnostic assessment ¹,²,³,⁴.