When children with autism struggle with behavior, it’s commonly attributed to speech issues or frustration associated with communication. But new research suggests that may not be the case.

A new study finds that less than 3 percent of tantrums among youngsters with autism are rooted in speech or language difficulties.

“There is a common pervasive misbelief that children with autism have more tantrum behaviors because they have difficulty communicating their wants and their needs to caregivers and other adults,” said Cheryl D. Tierney of Penn State Children’s Hospital who worked on the study published recently in the Journal of Development and Physical Disabilities. “But we found that only a very tiny percentage of temper tantrums are caused by having the inability to communicate well with others or an inability to be understood by others.”

For the study, researchers looked at 240 kids with autism ages 15 to 71 months with a range of speech and language capabilities. They assessed the children’s IQ and language skills and asked mothers about tantrum frequency and speech intelligibility.

The findings indicate that speech and language abilities largely failed to correlate with a child’s behavior. In fact, researchers noted that children with speaking ability on par with a typical 2-year-old displayed more tantrums than those with lesser speech skills.

While the study doesn’t address what is to blame for the tantrums, Tierney said they could result from mood dysregulation and a low tolerance for frustration.

“We should stop telling parents of children with autism that their child’s behavior will get better once they start talking or their language improves, because we now have enough studies to show that that is unlikely to happen without additional help,” she said.

Instead, Tierney recommended that parents seek out assistance from a behavior analyst.