Diagnosing Autism Spectrum Disorders in Primary Care: When You Know, You Know

Screening is indicated for conditions that can be accurately identified through screening, for which diagnosis can be accurately confirmed, and when earlier intervention leads to improved outcomes. In this issue of Pediatrics, McNally Keehn and colleagues report on the diagnostic accuracy of autism spectrum disorder diagnoses in preschool-aged children by primary care providers (PCPs) who have had additional training and coaching¹  in the context of a tiered statewide initiative to identify, diagnose, and care for children with autism.²  These authors evaluated the diagnostic accuracy of this approach to decreasing barriers that delay developmental diagnosis through an extensive learning cooperative with PCPs in regional hubs, trained to perform diagnostic evaluations for preschool children identified as at risk for autism through primary care surveillance and screening.

Listening to families’ concerns, along with surveillance and routine screening for autism, are the first steps on the path to intervention.³  Although the use of autism-specific screening tools in primary care has increased, they are often used incorrectly, and a minority of children who score at risk are referred for evaluation.⁴  Explanations for the low referral rate have included PCP belief that the child did not have autism, systemic barriers to the referral process, and lack of a process to monitor referrals.⁴  Referral for diagnosis is a critical next step, and PCPs should also not delay referring children for early intervention or preschool services. Service eligibility determination typically includes cognitive, language, and social-emotional evaluations that can both inform the diagnostic process and allow children to begin symptomatic intervention while awaiting diagnosis.³ 

A major barrier to a timely autism diagnosis is the prolonged wait from initial referral to specialist evaluation.⁵  McNally Keehn et al prospectively evaluated the accuracy of an approach that educates PCPs about autism and coaches them in a diagnostic assessment that combines developmental-behavioral history, medical examination, initial screening with the Modified Checklist for Autism in Toddlers, revised with follow-up questions, and assessment of behaviors using the Screening Tool for Autism in Toddlers, an interactive screening tool used to support Diagnostic and Statistical Manual of Mental Disorders, 5th Edition diagnosis of autism in 24- to 48-month-old children.⁶  A high level of agreement in diagnosis (82%) was demonstrated between PCPs and specialists.¹  However, the accuracy for true positives (PCP-identified autism) was greater than for the false negatives (PCP did not diagnose autism but specialists subsequently did). The agreement was greatest and the PCPs most confident when the child had more significant developmental delays.

Because autism is heterogeneous in presentation and the differential diagnosis broad, specialty evaluation remains necessary for children who have complex presentations, are older, and when concerns remain about a diagnosis. Developmental diagnoses are dynamic; symptoms, level of concern, and functional impact may change over time. Children who screen as being at risk but are not diagnosed with autism almost always have another developmental or behavioral diagnosis that would benefit from evaluation and intervention.¹ 

The purpose of universal screening, referral of children at risk, and timely diagnosis is to provide appropriate support and interventions as early as possible. Systemic inequities continue to affect the timeliness of autism diagnosis and use of services.^3,4,7  This study minimized barriers of cost, distance to tertiary care centers, and wait time for scarce diagnostic services in an English-speaking population who were identified and referred in the context of primary care. Ushering all families through the complex systems that lead to diagnosis, support, and intervention requires that medical, educational, and public health initiatives address racism, language, geography, finances, and other barriers families face.

PCPs need to be equipped to care for children after autism diagnosis and to address commonly cooccurring medical and behavioral conditions.³  Learning collaboratives, such as the one described by McNally Keehn et al,^1,2  and telementoring programs like Extension with Community Health Outcomes⁸  are valuable for expanding PCP skills and confidence in both diagnosis and care for individuals with autism. With a current prevalence of 1 in 36 children,⁹  it is critical that training programs enhance autism-focused education and clinical experiences so that physicians- and advanced practice providers-in-training enter practice with the expectation that they can and will participate in diagnosis and/or ongoing care of children and youth with autism and other developmental disorders.¹⁰  The field of Developmental Behavioral Pediatrics is prioritizing workforce development,¹¹  training both specialists needed for consultation and complex diagnostics and PCPs who will have the expertise to diagnose autism in young children as demonstrated by these¹  and other authors.^5,6,8  Ongoing research in the field is focused on the validation and feasibility of using the Screening Tool for Autism in Toddlers and other interactive tools in busy primary care settings.^12,13 

McNally Keehn, et al have taken an important giant step for the children of Indiana. They demonstrated that with appropriate training and tools and the collaborative efforts of PCPs and specialists within a structured and committed system, that PCPs can accurately diagnose autism in most preschool children, thus expanding workforce capacity and decreasing wait time for evaluation. Increasing access to diagnosis increases demands on the medical system for etiologic, medical, and behavioral care and the educational system for appropriate and equitable intervention. To meet the goal of earlier entry into services, improvements in access to diagnosis must be accompanied by increased access to effective interventions and family support.

PCP

primary care provider