Trained developmental-behavioral pediatricians can generally diagnose autism spectrum disorder (ASD) in young children without the need for additional Autism Diagnostic Observation Schedule (ADOS) testing, finds a prospective multicenter study. The study, conducted through the Developmental Behavioral Pediatrics Research Network (DBPNet) and led by Boston Children's Hospital, was published in JAMA Pediatrics.

The ADOS was originally developed as a research tool. Through semi-structured observations, specially trained evaluators assess children's communication skills, social interaction, and imaginative use of materials.

"The ADOS was never designed to be used in the clinic," says William Barbaresi, MD, the study's principal investigator and chief of the Division of Developmental Medicine at Boston Children's. "But currently, ADOS testing is often required for young children to receive an ASD diagnosis that is accepted by early intervention agencies, schools, and insurers. This study shows that in the majority of cases, young children may be able to have a diagnostic evaluation for ASD by a developmental-behavioral pediatrician without using the ADOS."

ADOS administration is time consuming, adds additional cost to the diagnostic process, and there are not enough people trained to administer it. "The requirement for ADOS testing has become a barrier to timely diagnosis and initiation of treatment," Barbaresi says. "Young children can wait months or even years for an assessment, making it difficult for them to access intensive early intervention services when they are most effective—ideally starting at around 24 months of age."

The study involved 349 children aged 18 months to 5 years who were evaluated at nine academic pediatric centers. Developmental-behavioral pediatricians (DBPs) first made a diagnosis based on their clinical assessment. A specially trained clinician then administered the ADOS, the results of which were shared with the DBP, who then could revise their diagnosis.

In 90 percent of cases, the diagnosis including the ADOS was consistent with the original clinical diagnoses. Consistency was most likely when the clinician felt highly certain of their original diagnosis.

"Overall, this study is good news," says Barbaresi. "We believe it has the potential to change current practice by reducing wait times for diagnostic evaluations so that children can receive early, intensive treatment for ASD."