Supposed gateway confirmation based on flawed reading of data
A new study has appeared in the advance online publication of the October issue of Nicotine and Tobacco Research, purporting to confirm that electronic cigarettes are a gateway to youth smoking of combustible cigarettes, on the basis of analysis of the CDC's National Youth Tobacco Study for 2011-2013. The supposed results have been plastered all over the press, but in fact the conclusion is achieved only through a pointedly misleading selection of data points.
The headlines blare that 43.9% of never smoking youth users of e-cigs declare an intent to smoke cigarettes in the future. But a close look at the survey response that is the pretext for this conclusion shows that the kids simply failed to say that they definitely would not smoke in the future.
"Youth reporting they would definitely not smoke in the next year or if offered a cigarette by a friend were defined as not having an intention to smoke, while all others were classified as having positive intention to smoke conventional cigarettes."
This refers to Question 10 of the survey:
"10. If one of your best friends were to offer you a cigarette, would you smoke it?
A. Definitely yes
B. Probably yes
C. Probably not
D. Definitely not"
This means that youngsters answering "Probably not" and "Probably yes" were included in the 43.9% along with the "Definitely yes" answers, and also along with those who did not answer the question. Not only does this invalidate the figure of 43.9%, but such shoddy methodology tends to discredit the entire article.
Given this lapse, the figure given for "never smoking e-cig users" is also suspect. This would be non-smoking youths who answered "G. Electronic cigarettes or E-cigarettes, such as Ruyan or NJOY" to the question: "Which of the following tobacco products have you ever tried, even just one time?" This hardly implies regular use of e-cigs.
Given that all other studies to date indicate the opposite, that youthful vapers are already smoking, this statistic will have to be at the very least confirmed by other studies.
Another way of stating the result would be to say that 56.1% of youths who have tried e-cigs ("even once") report that they would definitely never smoke a combustible cigarette, even if it were offered one by a close friend, while the remaining "e-cig experimenters" might do so. So a majority of experimenters have a definite intention not to smoke in the future, while a minority remains uncommitted on the issue. This is hardly the confirmation of gateway that has been gleefully trumpeted in the press. And it says nothing about teen smokers who also vape. Earlier studies have suggested that most of them are probably vaping to quit.