and (2) ever smoking and escalation were associated with e-cigarette initiation (ever e-cigarette use at follow-up) among baseline never e-cigarette users (n = 1,020)."

“... this study provides further support for the association between ever e-cigarette use and smoking initiation, and additionally finds that ever smoking is associated with e-cigarette initiation, among young people. A better understanding of these associations will aid policymakers with their efforts to develop an appropriate regulatory framework for both tobacco products and e-cigarettes.”

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