A test that’s often required for children to receive an autism diagnosis may be unnecessary and eliminating it could make the process faster, easier and cheaper, researchers say.

Many children undergo testing with what’s known as the Autism Diagnostic Observation Schedule, or ADOS, as part of an evaluation for autism. The assessment relies on specially trained clinicians to observe how children communicate, interact socially and behave while engaging in certain activities.

The test is a frequent expectation for insurance providers and others in order for children to access treatment for the developmental disorder, but it can be costly, time consuming and waiting to access the specialized testing can substantially lengthen the time it takes for a child to be diagnosed.

Now a new study published in the journal JAMA Pediatrics suggests that the assessment may not be needed.

Researchers looked at the experiences of 349 children ages 18 months to 5 years who were evaluated for autism at nine academic centers across the nation. All of the kids were first assessed by a developmental-behavioral pediatrician who made a determination before they then completed ADOS testing with a specially trained clinician.

The study found that in 90% of cases, the results of the ADOS assessment made no difference.

“The ADOS was never designed to be used in the clinic,” said Dr. William Barbaresi, chief of the Division of Developmental Medicine at Boston Children’s Hospital and the principal investigator of the study. “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.”

In cases where the developmental-behavioral pediatrician was highly certain of their original opinion, the final diagnosis was most likely to be consistent with their initial result, the study found.

“The requirement for ADOS testing has become a barrier to timely diagnosis and initiation of treatment,” said Barbaresi who noted that wait times for ADOS testing can be months or even years long, potentially delaying access to early intervention when it can be most effective. “We believe (this study) has the potential to change current practice by reducing wait times for diagnostic evaluations so that children can receive early, intensive treatment for ASD.”