The anti-vaping lobby is at it again, with a new study allegedly showing e-cigarettes encourage smoking and played no role in the recent and rapid declines in teen cigarette use.
Professor Stanton Glantz and Dr. Lauren Dutra at the University of California San Francisco claim the declining trend in adolescent cigarette smoking from 2009-2014 was no different from 2004-2009.
Based on these findings the authors argue there is no evidence e-cigarettes affected the decline in youth smoking, with Glantz asserting, “E-cigarettes are encouraging — not discouraging — youth to smoke and to consume nicotine, and are expanding the tobacco market.”
Does this mean the arduous search for evidence to prove the ‘gateway’ hypothesis has finally come to an end, and e-cigarettes really are creating a new generation of smokers?
Not even close. The first thing to point out is that the study’s own results directly contradict Glantz’s assertion. You cannot, on one hand, claim e-cigarettes had no effect on the downward trend of youth smoking and at the same time claim e-cigarettes are encouraging kids to smoke and expanding the tobacco market.
“You can’t tell just the half of the story that you happen to like,” writes Dr. Michael Siegel of the Boston University School of Public Health. “If this study provides evidence that e-cigarettes didn’t result in a decline in youth smoking because there was no change in the rate of decline then the study also provides evidence that e-cigarettes didn’t result in an increase in youth smoking.”
Even if the study’s findings are correct, they’re in direct conflict with the way the authors are trying to present them.
But there is an even more fundamental problem with the study, which proves awkward for the gateway narrative and casts doubt on the allegation that e-cigarettes had no impact on smoking trends.
Using data from the National Youth Tobacco Survey, the graph below from Glantz’s study shows the percentage of adolescents who used a cigarette or e-cigarette in the last 30 days.
The blue line shows the pre-2009 trend extrapolated into the future and is intended to illustrate the lack of impact e-cigarettes had on declining trends in youth cigarette use.
But according to Christopher Snowdon, the head of lifestyle economics at the Institute of Economic Affairs, the graph “doesn’t bear much resemblance to the NYTS data.”
“They claim that ‘Current smoking decreased from 15.8 percent in 2004 to 6.4 percent in 2014’ but the only reference Google can find to a smoking rate of 6.4 percent in 2014 comes from their own study,” says Snowdon.
The actual NYTS data shows a cigarette smoking rate of 9.2 percent among high school students in 2014 and 2.5 percent among middle school students. Correcting for this, Snowdon shows there is a substantial increase in the rate of decline after 2012.
“All the smoking rates since 2011 are lower than the pre-2009 trend would have predicted and the rate in 2014 is dramatically lower,” writes Snowdon, who created his own graph to illustrate the point.
The big surge in high-school e-cigarette use occurred between 2012-2014 when past month e-cigarette use rose from 2.8 percent to 13.4 percent, exactly when the unusually large declines in smoking occurred.
The choice of 2009 as the split point to test the before and after effect of e-cigarettes on smoking trends is a curious, according to Siegel, since almost no students in either high school or middle school vaped in 2009.
Siegel argues choosing 2009 as the split point “creates an artificially low estimate of the decline in youth smoking from 2011 to 2014.”
It should be noted that neither the NYTS nor similar surveys prove causality and we cannot say for certain whether e-cigarettes played a role in the rapid decline smoking among high school students.
But what the data do suggest is that Glantz and Dutra’s assertion that “there was a decline in current smoking that did not change after the introduction of e-cigarettes,” is plain wrong, or, at the very least, highly misleading.
Guy Bentley (@gbentley1) is a contributor to the Washington Examiner’s Beltway Confidential blog. He is a consumer freedom research associate at the Reason Foundation and was previously a reporter for the Daily Caller.