JAMA - "Association of Electronic Cigarette Use With Initiation of Combustible Tobacco Product Smoking in Early Adolescence"

"Association of Electronic Cigarette Use With Initiation of Combustible Tobacco Product Smoking in Early Adolescence"

"Conclusions and Relevance  Among high school students in Los Angeles, those who had ever used e-cigarettes at baseline compared with nonusers were more likely to report initiation of combustible tobacco use over the next year. Further research is needed to understand whether this association may be causal."

http://jama.jamanetwork.com/article.aspx?articleid=2428954