From Adam Smith Institute:
Writing earlier this year for The Washington Times, Carrie Wade and David Bahr of the R Street Institute explain:
Studies supporting the notion that kids who try vaping will dive head first into combustible use are critically flawed — they cannot control for kids who would end up smoking anyway and rarely acknowledge those who use e-cigarettes in the first place. In reality, vape use is highly concentrated in those who already smoke or have tried smoking.
Indeed, the National Academies of Science notes that associations between smoking and vaping do exist, but they are contradicted by population data citing opposing trends in e-cigarette and cigarette use among youth in recent years, and do not confirm person-level positive associations with vaping and smoking.