There’s not enough evidence that it’s beneficial to screen all young children for autism, a task force is arguing in a new report.

David Grossman, the vice chair of the U.S. Preventive Services Task Force, said that there wasn’t enough evidence that the benefits would outweigh the harms in screening children between the ages of 18 and 30 months, according to a CNN report.

Instead, individual clinicians need to make the call on a case by case basis, Grossman said. Still, the pronouncement is causing concern that it could result in some autistic children being missed early on.

Autism spectrum disorder is a developmental disability that impacts a child’s development when it comes to social, communication, and behavioral skills. About one in 45 children were diagnosed back in 2014, way up from one in 150 in 2000.

It’s not that the task force is against screening, it’s that without large, controlled studies, there’s no evidence such screenings would help identify children who otherwise wouldn’t be diagnosed with autism, the task force argued, instead advocating for more research and larger studies.

It’s certainly a controversial stance to take. The American Academy of Pediatrics disagrees, suggesting that testing for autism should be routine for pediatricians.

The findings were published in the Journal of the American Medical Association.

“Although a number of potential risk factors for ASD have been identified, there is insufficient evidence to determine if certain risk factors modify the performance characteristics of ASD screening tests, such as the age at which screening is performed or other characteristics of the child or family,” reads a statement from the task force. “The USPSTF concludes that there is insufficient evidence to assess the balance of benefits and harms of screening for ASD in children age 18 to 30 months for whom no concerns of ASD have been raised. Evidence is lacking, of poor quality, or conflicting, and the balance of benefits and harms cannot be determined.”