Recommended Screening Ages for Autism, ADHD, and Behavioral Disorders
Children should be screened for Autism Spectrum Disorder (ASD) at 18 and 24 months of age, while ADHD and behavioral disorders are typically screened for after age 4. 1, 2
Autism Spectrum Disorder (ASD) Screening
Recommended Screening Timeline
- The American Academy of Pediatrics (AAP) recommends universal ASD-specific screening at 18 and 24 months of age during routine well-child visits 3
- Siblings of children with ASD require intensified surveillance with screening at minimum at 18 and 24 months due to their elevated risk (14-18%) 3, 4
- Some signs of ASD can be detected as early as 12 months, though screening before 18 months may have higher false-positive rates 3, 5
Screening Tools by Age
- For children 16-30 months: Modified Checklist for Autism in Toddlers (M-CHAT) is recommended as both a level 1 and level 2 screening tool with strong evidence supporting its use 3, 1
- For children around 12 months: Communication and Symbolic Behavior Scales Developmental Profile (CSBS DP) Infant/Toddler Checklist can detect communication delays that may indicate ASD 1, 4
- For high-risk children aged 14-36 months: Screening Tool for Autism in Two-Year-Olds (STAT) shows high sensitivity (92%) and specificity (85%) 3, 1
Important Considerations
- Diagnostic stability of ASD in children diagnosed at 18-24 months is promising, with studies showing 82.6-91.8% stability when reassessed at age 3 6
- Children diagnosed with ASD at later ages (25-41 months) often show more severe impairments in cognitive, adaptive, and social functioning than those diagnosed earlier 7
- Early detection allows for timely intervention, which can significantly improve developmental outcomes 4, 8
ADHD and Behavioral Disorders Screening
- Unlike ASD, formal screening for ADHD is not typically recommended before age 4, as symptoms may not be reliably distinguished from normal developmental variations in younger children 2
- Behavioral disorders are similarly difficult to diagnose reliably before preschool age, with most screening tools validated for children 4 years and older 2
Early Warning Signs to Monitor (12-24 months)
- Reduced social attention, including decreased eye contact and diminished response to name by 12 months 9, 4
- Limited or absent joint attention behaviors (inability to share focus with others about objects or events) 9
- Decreased use of gestures for communication, such as pointing or waving 9, 4
- Repetitive actions or posturing of body, arms, hands, or fingers 9
- Unusual sensory interests or sensitivities 9
Common Pitfalls in Early Detection
- Waiting for language delay as the primary indicator of ASD, when social communication differences often appear earlier 9
- Failing to recognize the variability in symptom onset and developmental trajectories 9
- Missing the opportunity for early intervention by delaying screening until preschool age 4, 8
- Not following up on initial positive screening results with comprehensive evaluation 7
Clinical Approach to Developmental Screening
- Implement universal ASD screening at 18 and 24 months using validated tools like M-CHAT 3, 2
- Conduct ongoing developmental surveillance at all well-child visits 3, 2
- Immediately refer children who screen positive for ASD for comprehensive diagnostic evaluation and appropriate early intervention services 3
- For siblings of children with ASD, maintain heightened vigilance with continuous developmental surveillance 3
- Consider earlier screening (12-15 months) for children with multiple risk factors or concerning signs 4, 5