by Carl V Phillips
Perhaps as a tribute to our nation’s great accredited schools of public health, the Florida Department of Health recently blasted the world with junk science claims based on incorrect research methods and basic innumeracy. What they were trying to do was issue dire warnings about children using e-cigarettes, but mostly I think they succeeded in issuing a different warning to parents: Do not let your children study public health!
The Florida exaggerations are already being used in anti-e-cigarette propaganda. For example, they appear in the actual language of the bill to effectively ban e-cigarette sales in NYC (it would ban flavors, which are obviously rather critical to the product.) (See this recounting of the language.) The claim was that 40% more high school students tried e-cigarettes in 2012 than the year before, which is not actually what the data shows. According to the Florida DoH Fact (sic — and LOL) Sheet about this (not dated, but clearly from earlier this month since that was when it was press-released), their surveys found that 6.0% of such students had tried an e-cigarette in their 2011 survey and 8.4% in 2012, which they described as a “40.0%” increase. Numerate readers will immediately notice that (a) the uncertainty in the survey means that there is absolutely no way they can make a claim with three significant figures and (b) the third digit is undoubtedly wrong, and probably the second too, since they apparent rounded the other results to two sig figs and then did the calculation. (Credit to the above news story for correctly rounding this to 40%.) So, basically, public health people lack grade 7 level math/science training.
Rather worse in their reporting is describing this ever use statistics as “prevalence of this behavior”, meaning they did not understand the one semester of epidemiology they took in public health school either. The word “prevalence” is inappropriate, and thus misleading, when describing an “ever” statistics. Since “ever” ratchets (once you are in that category, you can’t go back), it is basically inevitable that there will be an increase in a population that is 3/4 the same people from one year to the next. This misreporting may partially explain why the equally innumerate people in the NYC Health Department misinterpreted the result (lied) by saying the number who tried e-cigarettes that year had increased by 40%. And, of course, if they had emphasized the more useful number, that 8% of high school students reported ever having tried an e-cigarettes, even just one puff, the number would not have been impressive at all.
The statistics are not legitimately reported even if we believe the point estimates are exactly right. After we consider random sampling error (not reported), response bias (clearly a problem, but completely ignored), and measurement error (I know that I always gave random data when asked to do some intrusive survey like this when I was in school) the results are pretty meaningless. The only reason that we should believe the trend at all (that there has been an increase) is that it is pretty much inevitable, not because if their data. Needless to say, given these basic errors in reporting, we should doubt the accuracy of their numbers also.
But even if we start with their basic numbers and ignore their errors and sensationalism, what can we make of it? How many of those who tried e-cigarettes were regular smokers? Quite possibly all of them, since the rate of current smoking is higher than the number who have merely tried an e-cigarette, but we will never know because they suppressed that information (which they apparently do have). How many of them had tried at least one puff of a cigarette? I would guess approximately all. How many of them are of legal age to use tobacco products, as many high school students are? Again, they intentionally hid all that information. It is difficult to see such obvious omissions as mere incompetence — they are clearly intended to mislead readers.
Similarly, they lied about current use. They did this mainly by referring to “tried at least one puff in the last 30 days” as “current use”. Moreover, their numbers for recent trying (which is what this really is, not “use”) are very low — half or less the figures for “ever tried”. So, of course, the propagandists did not mention them, hoping that sloppy readers would mistake “ever tried” for “uses”.
It is interesting to note that as a portion of those who had ever tried, those who had taken one puff within 30 days dropped substantially from 2011 to 2012. Since many of those who have only tried e-cigarettes on a few occasions must have done so within any given month, this shows that a rather small fraction of those who have tried an e-cigarette did it very often after that (let alone qualified as genuine “current users”). This is especially true for the 1.8% of middle school students who had tried in the last month (compared to 3.9% who had ever tried), since they would have had relatively few total months in their history that they might have tried them. Nevertheless this was breathlessly reported as having “increased by 20.0%” (emphasis and that same sig fig error in the original), and it is that statistics that has been repeated in subsequent propaganda, rather than the low absolute numbers.
What can we make of this? Well, we know what the ANTZ want to make of it, as quoted in the press release (attributed to the American Cancer Society):
We do know that e-cigarettes can lead to nicotine addiction, especially in young people who may be experimenting with them, and may lead kids to try other tobacco products, many of which are known to cause life-threatening diseases.
Of course, we most certainly do not know that e-cigarettes can lead to addiction. There is not the slightest piece of evidence to support that claim. Notice that the Florida data itself shows that most of those who try e-cigarettes have not tried one in the last month — if this is addiction, then that ANTZ word has become even more meaningless than it was before. Nor is there any evidence that e-cigarettes cause anyone to use other tobacco products. And, of course, only cigarettes and their minor variations (not “many” products) are known to cause life-threatening diseases (though it was amusing to see the implicit claim in that that e-cigarettes do not cause such diseases).
Honest people looking at this data can conclude almost nothing meaningful, other than that e-cigarettes exist. Is it possible that all the students who are using e-cigarettes are current or former regular smokers using them for THR? Yes — it is consistent with what was reported that every last one of them is. Could experimentation with e-cigarettes be causing other net reductions in risks in this population? Yes — those who are experimenting are the ones who are most likely experimenting with other drugs or behaviors that can do a lot of harm. If using an e-cigarette is displacing underage drinking, it is contributing even more to harm reduction than it does when it displaces smoking.
E-cigarettes are used by people almost exclusively to replace a much more harmful behavior. Students are people. Why then, exactly, is the assumption that when they are using them, there is net harm? Of all the drugs or other youthful dalliances that kids might be engaging in, it is difficult to imagine one that is less harmful than e-cigarettes (or smokeless tobacco), except maybe coffee, and even then it is not clear which is less harmful.