In the largest look ever at autism and bullying, new research shows that children on the spectrum are significantly more likely than other kids to be bullied.

Researchers polled nearly 1,200 parents across the country and found that 63 percent of kids with autism have been bullied. What’s more, some 39 percent of parents said their child with autism had been bullied within the last month compared to just 12 percent of typically developing siblings.

While many within the autism community have long believed that bullying is an especially acute problem for those with the developmental condition, the preliminary findings released Monday add to a growing body of scientific evidence on the topic.

“Even though I expected it to be a big problem, it was bigger than I even thought,” said Connie Anderson, community scientific liaison at the Interactive Autism Network, a national autism registry at the Kennedy Krieger Institute which conducted the ongoing survey.

With concrete findings, the researchers say they hope policymakers and educators can be encouraged to take steps to address the issue.

For the survey, parents across the country were asked about the bullying experiences of their kids with autism ages 6 to 15 and about the experiences of their typically developing children within the same age group. Findings reflect the experiences of 1,167 kids with autism and 795 children without.

Overall, those with autism were more likely to be bullied in fifth through eighth grade and kids attending regular public school were 50 percent more likely to be bullied than those enrolled in private schools or special education environments, the survey found.

Certain attributes also appeared to play a role. Specifically, kids with autism who are inflexible, have frequent meltdowns and those who talk obsessively about particular topics are at higher risk, researchers said.

In most cases, parents reported that children who were bullied were teased, picked on or made fun of. In other instances, kids were ignored, left out, called names or subject to pushing, hitting, kicking or slapping.

Kids with autism aren’t just victims of bullying, however. In 17 percent of cases, parents said that their children were both subject to and had been accused of being bullies themselves.

“I hope this is really good evidence for society at large that this is a problem,” said Anderson, who in addition to her research role is also the parent of a child with autism who has been bullied. “It’s really sad to know that this is going on.”

Analysis of the survey is ongoing and the researchers said they plan to submit final findings to a peer-reviewed journal within the next year.