Teens who use e-cigarettes are more likely than their peers who do not use the devices to smoke regular cigarettes, a new study finds. They are also less likely to quit smoking, The New York Times reports.

Experts disagree about the implications of the findings, the article notes. Stanton Glantz of the University of California, San Francisco, who led the study, said the results suggest e-cigarettes lead to less quitting. “The use of e-cigarettes does not discourage, and may encourage, conventional cigarette use among U.S. adolescents,” the researchers wrote in the journal JAMA Pediatrics.

In a news release, Glantz said, “It looks to me like the wild west marketing of e-cigarettes is not only encouraging youth to smoke them, but also it is promoting regular cigarette smoking among youth.”

Other experts said it is possible young people who use e-cigarettes are heavier smokers to begin with, or would have become heavy smokers anyway. They add e-cigarettes may not be the cause of teens’ problems with quitting smoking.

While some experts say e-cigarettes may help people quit smoking regular cigarettes, others are concerned the devices are a gateway to smoking real cigarettes.

A large government survey published last year found many young people who use e-cigarettes also smoke real cigarettes. While e-cigarette use among teens doubled from 2011 to 2012, use of regular cigarettes among this age group hit a record low of 9.6 percent in 2013, according to the newspaper.