Most children who screen as being at an increased likelihood of autism are not referred to specialist care, a scoping review in Pediatrics found.

That reality, reported by Shana M. Attar, MS, of the Department of Psychology at the University of Washington in Seattle, and colleagues, contrasts with the American Academy of Pediatrics’ recommendation for universal autism screening at 18- and 24-month well-child checkups and immediate referral of all indicated children for diagnostic evaluation, early intervention, and audiology.

The authors noted that over the past two decades, the median age of autism diagnosis in the United States has decreased by just 2 months, and early autism-specific services have an estimated utilization rate of just 50% for indicated young children. Because primary care pediatricians and general practitioners serve as the gatekeepers to specialized care, their scoping review synthesized generalist providers’ decision-making processes for referrals of young children aged 0-5 years.

“New innovations in diagnosis are emerging, but we need more information about how families are supported through the diagnostic process,” study co-author Sarabeth Broder-Fingert, MD, MPH, a professor of pediatrics at UMass Chan School of Medicine in Worcester, Massachusetts, told Medscape Medical News.

She added that referral rates were lower than she anticipated. “The reasons for low referral rates were not surprising, though. Given the lack of diagnostic services, it’s no surprise that pediatricians don’t want to refer kids to long waitlists or unavailable services.” 

In the 38 studies examined by the review, referral rates varied widely, ranging from over 1% to almost 100%, depending on the practice, referral site, and referral setting — that is, whether referrals were reported in routine clinical care or after targeted intervention.

“Perceived symptom severity and greater caregiver concern were associated with increased referral rates,” the authors wrote. Barriers noted included providers’ lack of confidence in screening tools and lack of local diagnostic and intervention sites.

The review found that in studies that had no intervention component, providers referred children to evaluations and early intervention services at rates ranging from 20% to 58.4%. In intervention studies, referral rates ranged from 45% to 98% post-intervention.

In another recent analysis of 290 pediatricians across 54 primary care practices, screening rates were reported as 93% at 18-month wellness visits and 82% at 24-month visits, but referral rates of children indicated for specialist evaluation were much lower at 31%. 

Similarly, a 2020 retrospective chart review of 2822 toddlers in pediatric primary care who screened at elevated risk on a standardized autism screening at their 16-month wellness checkup found that physicians referred only 40.2% of indicated children to at least one of three recommended services. Only 3.7% of indicated children were referred to all three services, thereby diminishing the effectiveness of screening. “Unfortunately, screening administration in isolation confers little benefit to children and families,” the authors wrote.

Offering a nonparticipant’s perspective on the referral issue, Mary Beth Miotto, MD, MPH, FAAP, a pediatrician in Boston, told Medscape Medical News that referrals from primary care to specialist care continue to face headwinds for both parents and pediatricians. “When I was working with a national team in 2015 to increase the screening and diagnostic rates for developmental concerns, every healthcare team in our program identified referrals as their biggest challenge,” she said.

While the causes of backlogs are diverse, including insufficient diagnosticians and differing regional practice customs, Miotto has nevertheless seen substantial progress. “Parents are much more open to both the screening and the referrals, although there are families who are not quite ready for the specialty referral, and then the primary care physician will continue to keep in close touch to help them.” But if anything, she said, increased developmental screening rates and awareness may have increased the bottleneck for diagnosis. 

The biggest barrier to consistent referral is capacity, Miotto said. “There have been times when the waitlists got so long that certain autism centers were closed to referrals for months on end. When this happens, a community pediatric or family medicine team may lose access to their only referral center.”

She would like to see more time available for pediatricians, family physicians, and advanced practice clinicians “to listen to families, have a discussion that is meaningful and family-centered but scientifically correct, and continue to grow trust from visit to visit.” 

According to the authors of the study, new research efforts should focus on increasing early intervention, which is appropriate even for false-positive children screening at elevated likelihood of autism. In addition, rigorous studies that optimize referral processes across providers and settings are needed.

But the abiding obstacle is resources, said Broder-Fingert. Creating more supply — high-quality diagnostics and support services for families and more training for primary care providers — would likely improve referral rates. But would there then be enough trained specialists to treat affected children? “Not even close,” she said. “The workforce needs to be tripled at least.”

Her group is currently working to train primary care pediatricians to diagnose autism. “We think this is a great way to expand the workforce. We also need better reimbursement rates for autism diagnostic assessments.” 

This research was supported by the National Institute of Mental Health of the National Institutes of Health. A subscription to Covidence, a web-based program provided by the University of Washington that facilitates literature reviews, was used in this analysis. The authors and Miotto reported no conflicts of interest.