To examine associations between referral concerns, screening results, and diagnostic outcomes for young children evaluated across a statewide primary care network for early screening and diagnosis of autism spectrum disorder (ASD).

The Early Autism Evaluation Hub system was developed to increase developmental screening and improve access to timely ASD evaluations in local communities. In 2019, 858 children (ages 18-48 months; 40% diagnosed with ASD) received ASD evaluations across 12 Early Autism Evaluation Hubs. Data on primary care provider (PCP)- and caregiver-reported referral concerns, Modified Checklist for Autism in Toddlers, Revised with Follow-Up (MCHAT-R/F) and Ages and Stages Questionnaire, Third Edition (ASQ-3), and diagnostic outcome were collected.

Among children evaluated, there was low concordance between PCP and caregiver referral concern. Although a positive MCHAT-R/F screen was associated with PCP but not caregiver-reported ASD referral concern, there was a significant linear relationship between MCHAT-R/F raw scores and both PCP and caregiver ASD referral concern. A different pattern of ASQ-3 delays was found to be associated with PCP-reported as compared with caregiver-reported ASD referral concern. Finally, PCP-reported ASD referral concern, positive MCHAT-R/F, and ASQ-3 Communication and Personal Social delays were associated with a significantly higher likelihood of subsequent ASD diagnosis.

Understanding how community PCPs use surveillance and screening data, the extent to which PCPs and caregivers have shared understanding and engage in collaborative decision-making about evaluation referral, and how these factors relate to diagnostic outcomes has the potential to impact educational efforts for both PCPs and caregivers of young children, as well as inform the development of more efficacious early identification approaches.