The rate of teens who said they’ve ever tried vaping marijuana more than doubled between 2013 and 2020, from 6.1% to 13.6%, according to a new analysis of studies reported in JAMA Pediatrics.

Researchers analyzed 17 studies conducted in the United States and Canada, with a total of almost 200,000 teens. They found past-year marijuana vaping doubled from 2017 to 2020 — from 7.2% to 13.2%. The percentage of teens who said they had vaped marijuana in the past month rose from less than 2% to more than 8%.

Teens’ preference for cannabis products may be shifting from less potent products like dried herbal cannabis to highly potent vape oil and concentrates, the researchers noted.

“I can’t say I’m surprised by the meteoric rise in marijuana vaping among adolescents, given the substantial shift in public attitudes about marijuana’s safety, the increasing availability of unregulated vaping products, and the stealth nature of vaping versus smoking marijuana,” Linda Richter, Ph.D., vice president of prevention research and analysis at Partnership to End Addiction, told HealthDay. “Adolescents, along with adults, have been lulled into a false sense of safety about marijuana.”