To the Editor In their study, Dutra and Glantz1 reported the results of a cross-sectional sample of adolescents interviewed in 2011 and 2012 in the National Youth Tobacco Survey and concluded that electronic cigarette (e-cigarette) use does not discourage and may encourage conventional cigarette use among US adolescents.
However, their conclusions are not justified by the data presented. In a cross-sectional study, the observed relationship between e-cigarette use and higher and more sustained levels of smoking does not imply causation. Moreover, such studies do not take into account other population characteristics, which may play a crucial role when determining potential causation.2,3 Although the authors acknowledged this limitation in the text, they ended up drawing a conclusion that misleads the public into thinking e-cigarettes are leading to smoking initiation and addiction among adolescents.
Farsalinos KE, Polosa R. Youth Tobacco Use and Electronic Cigarettes. JAMA Pediatr. 2014;168(8):775. doi:10.1001/jamapediatrics.2014.727