Pediatric Pearls: Lack of Follow-Through on Referrals May Delay ASD Diagnoses in Children


  • Answer: Despite recommendations for early screening, the average age of ASD diagnosis in the United States is 4 years.

    The American Academy of Pediatrics recommends that all children be screened for autism spectrum disorder (ASD) at the 18- and 24-month well visits using an autism-specific screening tool in addition to routine developmental surveillance.1 The Modified Checklist for Autism in Toddlers (M-CHAT) is a common tool used by primary care practices to screen for ASD. If a child fails the screening, it is recommended that the child be referred for intervention and a diagnostic evaluation. Literature supports that early identification and treatment of ASD may improve developmental outcomes. Despite recommendations for early screening, the average age of ASD diagnosis in the United States is 4 years.2

    The Research

    A study published in Pediatrics by Monteiro and colleagues3 highlights the discrepancy between rates of ASD screening and referrals for further evaluation. For their study, the authors reviewed the medical records of children eligible for M-CHAT screening at the 18- and 24-month well visits at 54 primary care pediatric practices over a 2-year period.

    Of these eligible children, 93% were screened at the 18-month visit and 82% were screened at the 24-month visit. A total of 530 children (3%) failed one or both M-CHAT screenings. Of the children with failed screening, 12% were already receiving early intervention.

    The Results

    Overall, 20% of children were referred to early intervention, 16% to private therapy, and 36% to audiology. However, only 165 (31%) were referred to a specialist for additional evaluation. Some of these referrals were not followed through to completion. Children with ASD who were referred for evaluation at or before the 18- or 24-month visits (early referrals) received a diagnosis at an average of 27 months. Children with ASD who were referred after the 24-month visit (late referrals) received a diagnosis at an average of 43 months.  

    In summary, this study shows that physicians have been successful in administering autism-specific screening tools to identify children at risk for ASD. However, barriers still exist between a failed screening and a diagnosis. Many children with failed screens are referred for developmental intervention, but the rates of referral for diagnostic evaluation are low. The diagnostic evaluation is important and may allow a child to access targeted behavioral interventions with a diagnosis.

    Monteiro and colleagues propose using the M-CHAT with follow-up interview to improve positive predictive value of the screening tool, as well as implementing a best practice alert in the electronic medical record to notify a provider for a failed score and to advise next steps.

    Bottom Line—This study reminds us to both identify children at risk for ASD and refer appropriately for intervention and evaluation.


    1. Johnson CP, Myers SM; the Council on Children With Disabilities. Identification and evaluation of children with autism spectrum disorders. 2007;120(5):1183-1215. Pediatrics.
    2. Baio J, Wiggins L, Christensen DL, et al. Prevalence of autism spectrum disorder among children aged 8 years – Autism and Developmental Disabilities Monitoring Network, 11 sites, United States, 2014. MMWR Surveill Summ. 2018;67(6):1-23.
    3. Monterio SA, Dempsey J, Berry LN, Voigt RG, Goin-Kochel RP. Screening and referral practices for autism spectrum disorder in primary pediatric care. 2019;144(4):e20183326.