From the Guidelines
Autism Spectrum Disorder (ASD) can be diagnosed as early as 12 months of age.
Key Points
- The diagnosis of ASD is typically made when the requisite DSM-5 symptoms are present and other disorders have been adequately ruled out 1.
- Early identification is crucial, as many early autism signs can be reliably detected by 12 months, and potentially 50% of autism cases can be identified before 15 months 1.
- The American Academy of Child and Adolescent Psychiatry recommends that the developmental assessment of young children and the psychiatric assessment of all children should routinely include questions about ASD symptomatology 1.
- The DSM-5 criteria for ASD include onset in the early developmental period, focusing on social communication and interaction deficits and restricted, repetitive patterns of behaviors and interests 1.
- Some studies suggest that pointing for interest and use of conventional gestures can consistently differentiate autistic children from language-impaired peers at 20 and 42 months of age 1.
- At 36 months, items such as use of other’s body, attention to voice, pointing, and finger mannerisms can correctly classify children with autism 1.
- Early intensive behaviorally based interventions have been shown to be effective for many children, and age at intervention start improves outcomes 1.
From the Research
Age of Autism Spectrum Disorder (ASD) Diagnosis
- Autism Spectrum Disorder (ASD) can be diagnosed as early as 18 months of age 2, 3
- The average age of diagnosis ranges from 2.7 to 7.2 years 3
- Some children may not be diagnosed until after age 5, with a study finding that some children who did not meet ASD criteria at 3 years of age later met criteria in middle childhood 4
- Early diagnosis is critical, as it allows for earlier intervention, which can improve long-term outcomes for the child, family, and community as a whole 5, 2
Factors Associated with Early Diagnosis
- Delay in social communication or the presence of intellectual disability may be associated with an earlier diagnosis of ASD 3
- Children of parents who are together are diagnosed 1.4 years earlier than those whose parents are not together 2
- Baseline adaptive skills and female sex may be associated with non-persistence of ASD diagnosis 6
Importance of Early Screening and Surveillance
- Screening and surveillance schedules should extend past 36 months to detect ASD in children who may not show obvious symptoms until later in life 4
- Continued evaluation of any child who presents with atypical early development and/or high-risk status is necessary to ensure early diagnosis and intervention 4