A new study, published online ahead of print in the Journal of Adolescent Health, is being used by its authors to mislead the public into thinking that there is now evidence that electronic cigarettes are leading to smoking initiation and addiction among adolescents.
(See: Lee S, Grana RA, Glantz SA. Electronic cigarette use among Korean adolescents: a cross-sectional study of market penetration, dual use, and relationship to quit attempts and former smoking. Journal of Adolescent Health 2013; doi: 10.1016/j.jadohealth.2013.11.003.)
In a statement accompanying the study, study author Stanton Glantz proclaims that electronic cigarettes are "a new route to smoking addiction for adolescents."
He also represents his data as showing that: "kids who use e-cigs are less likely to have stopped smoking."
Glantz writes: "Use of e-cigarettes is associated with heavier use
of conventional cigarettes, which raises the likelihood that actual use
of e-cigarettes may increase harm by creating a new pathway for youth
to become addicted to nicotine and by reducing the odds that an
adolescent will stop smoking conventional cigarettes.”"
Glantz concludes: "We are witnessing the beginning of a new phase of the nicotine epidemic and a new route to nicotine addiction for kids."
The Rest of the Story
The rest of the story is that what we are actually witnessing is not the demonstration that electronic cigarettes are a route to smoking addiction for adolescents, but the twisting, manipulation, and misrepresentation of scientific data in order to mislead the public.
The problem is that Glantz is taking results from a cross-sectional study and misrepresenting them as if they were derived from a longitudinal study. Moreover, he is failing to heed his own warning, buried in the fine print of the paper, that: "Because the [survey] used cross-sectional data, the directionality of our findings cannot be established."
By examining the two major so-called "findings" of the study, you'll be able to see how Glantz is misrepresenting the study's actual findings.
1. "Kids who use e-cigs are less likely to have stopped smoking."
This conclusion is scary, and if true, I would have to think seriously about whether to continue to support electronic cigarettes as a smoking cessation strategy. The statement suggests that in this study, smokers who used electronic cigarettes were less likely to have quit over time than smokers who did not use electronic cigarettes.
There's just one problem: this study did not follow any smokers over time.
Despite the author's insinuation that this was a longitudinal study and that smokers who used electronic cigarettes were less likely to have stopped smoking over time, the study was in fact cross-sectional. It was a snapshot of tobacco/e-cigarette use behavior at a single point in time.
In fact, it did not assess whether any of the respondents had quit smoking, because it did not determine whether youth who did not currently smoke were ever current smokers. A youth could have puffed one time on a cigarette at a party and never smoked again, yet this individual would be considered a "former smoker" in this study.
Because the study is cross-sectional, there are two - not one - potential explanations for the observed association.
One possibility is as Glantz concludes: it is possible that smokers who used electronic cigarettes were less likely to quit over time.
But there is a second possibility: it could be that kids who experimented with cigarettes but did not begin smoking were not interested in starting to use electronic cigarettes. In other words, the causation could work in the opposite direction. The reason for the observed association between the use of electronic cigarettes and a greater chance of being a current than a "former" smoker could be simply that smokers are overwhelmingly more interested in electronic cigarettes than nonsmokers.
In fact, this is quite a likely possibility, as the study reports that current smokers are 66 times more likely than never smokers to be current electronic cigarette users.
In summary, the "actual" finding of the study is that there was an association between being a current as opposed to a former smoker and using or having used electronic cigarettes. But Glantz instead reports the interpretation that he apparently "wants" to believe: that kids who use e-cigs are less likely to have stopped smoking. He fails to inform readers of the equally likely (probably more likely) possibility that electronic cigarette use simply appeals much more to smokers than to kids who are not currently smoking.
2. "Use of e-cigarettes is associated with heavier use
of conventional cigarettes, which raises the likelihood that actual use
of e-cigarettes may increase harm by creating a new pathway for youth
to become addicted to nicotine."
This conclusion is scary, and if true, I would have to think
seriously about whether to continue to support electronic cigarettes as a
smoking cessation strategy. The statement suggests that in this study,
the use of electronic cigarettes caused smokers to smoke more, thus enhancing their addiction to cigarette smoking.
There's just one problem: this study was cross-sectional so it cannot conclude whether electronic cigarette use caused kids to smoke more or whether kids who smoked more were more likely to try electronic cigarettes (perhaps because they wanted to quit or cut down).
Once again, because the study is cross-sectional, there are two - not one - potential explanations for the observed association.
One
possibility is as Glantz concludes: it is possible that the use of electronic cigarettes led smokers to significantly increase their cigarette use, and thus to enhance their nicotine and smoking addiction.
But
there is a second possibility: it could be that kids who smoked more heavily were more likely to want to try electronic cigarettes, perhaps in an attempt to quit or cut down. In other words, the causation
could work in the opposite direction. The reason for the observed
association between the use of electronic cigarettes and a greater
chance of being a heavy smoker could be simply that
heavier smokers are more interested in electronic cigarettes than
lighter nonsmokers.
In fact, this is quite a likely
possibility, as the study reports that current smokers who are trying to quit are much more likely to use electronic cigarettes.
In
summary, the "actual" finding of the study is that there was an
association between being a heavier smoker and
using electronic cigarettes. But Glantz instead reports
the interpretation that he apparently "wants" to believe: that electronic cigarettes are causing kids to smoke more. He fails to inform
readers of the equally likely (probably more likely) possibility that
electronic cigarette use simply appeals much more to heavier smokers, perhaps because they are trying to quit or cut down.
The Study Conclusion
Ultimately, the study and Glantz' statement conclude that electronic cigarettes are "a new route to smoking addiction for adolescents."
However, this is a cross-sectional study, and it did not find a single youth who started using electronic cigarettes and then went on to become a regular cigarette smoker.
How then, can the study conclude that youths are starting with electronic cigarettes and then going on to be addicted to smoking?
The answer is simple: it can't.
The study was cross-sectional so it cannot determine whether the dual users in the study had initiated with electronic cigarettes and then went on to smoke, or whether they initiated with smoking and then went on to try electronic cigarettes.
But that didn't stop the study authors from drawing this conclusion.
Why Continue to Do Tobacco Control Research?
As we go into the Thanksgiving holiday, I am seriously thinking about why there is a need to continue to do tobacco control research. If we are going to simply conclude what we want to conclude, regardless of the ability of the science to reach such a conclusion, then what's the point of doing the research in the first place?
A lot of money (in this case, taxpayer money) could have been saved if we had simply told Dr. Glantz: don't bother doing the study. Just come out with your pre-determined conclusion. It will save the government and the taxpayers a lot of money and you're going to reach this conclusion anyway, regardless of whether the study design allows you to draw such a conclusion.
Seriously: why not just have anti-smoking researchers save a lot of time and money by simply disseminating their conclusions about how evil electronic cigarettes are, without actually conducting the research? The money saved could go into a fund that would be used for tobacco control education and prevention programs. This would be a win-win-win. Electronic cigarette opponents could continue to disseminate their unsupported conclusions, since the actual results of these studies don't matter anyway, and as an added bonus, taxpayers save money and funds are generated to further reduce smoking rates.
The rest of the story is that the findings of this study have been misrepresented to support what appears to be a pre-determined conclusion. The study is cross-sectional, and as the authors themselves acknowledge, it does not permit the very causal conclusions that they have drawn. The scary findings about kids being less likely to quit and more likely to smoke more because of electronic cigarette use could simply be a reflection of the possibility that kids who smoke, and who smoke more heavily, are more attracted to electronic cigarettes, perhaps because they want to quit or cut down on the amount they are smoking.
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