INTRODUCTION: Adolescents' use of electronic cigarettes (e-cigarettes) and exposure to e-cigarette TV advertising have increased in recent years, despite questions about their safety. The current study tests whether exposure to e-cigarette TV advertisements influences intentions to use e-cigarettes in the future and related attitudes. METHODS: A parallel-group randomized controlled experiment was conducted and analyzed in 2014 using an online survey with a convenience sample of 3,655 U.S. adolescents aged 13-17 years who had never tried e-cigarettes. Adolescents in the treatment group viewed four e-cigarette TV advertisements. RESULTS: Adolescents in the treatment group reported a greater likelihood of future e-cigarette use compared with the control group. ORs for the treatment group were 1.54 (p=0.001) for trying an e-cigarette soon; 1.43 (p=0.003) for trying an e-cigarette within the next year; and 1.29 (p=0.02) for trying an e-cigarette if a best friend offered one. Adolescents in the treatment group had higher odds of agreeing that e-cigarettes can be used in places where cigarettes are not allowed (OR=1.71, p<0.001); can be used without affecting those around you (OR=1.83, p<0.001); are a safer alternative to cigarettes (OR=1.19, p=0.01); and are less toxic (OR=1.16, p=0.03). CONCLUSIONS: Exposure to e-cigarette advertising had relatively large and consistent effects across experimental outcomes. Together with the simultaneous increase in e-cigarette advertising exposure and e-cigarette use among adolescents, findings suggest that e-cigarette advertising is persuading adolescents to try this novel product. This raises concerns that continued unregulated e-cigarette advertising will contribute to potential individual- and population-level harm
