On 2017 Feb 04, Carl V Phillips commented:

None

On 2017 Jan 25, Peter Hajek commented:

The press release claimed that ‘E-Cigarettes are Expanding Tobacco Product Use Among Youth’ but this study showed no such thing. It detected no increase in youth smoking, on the contrary, the continuous decline in smoking shows that e-cigarettes are not expanding smoking.

In fact, the data in the paper suggest that if anything, the increase in vaping has been associated with an accelerated decline in smoking. The cut-off point of 2009 seems to have been selected to show no acceleration, but very few young people tried vaping in 2009. By 2011, only 1.5% of middle and high school students vaped within the past 30 days and the figures went up after that. If the decline in smoking over 2004-2011 is compared with the decline over following years, it may well have significantly accelerated.

The final conclusion that ‘E-cigarette–only users would be unlikely to have initiated tobacco product use with cigarettes’ makes no sense because e-cigarette only users have not initiated any tobacco product use!

If the authors mean by this that they initiated nicotine use, this is unlikely. In this as in other similar reports, smokers were asked on how many days they smoked in the past 30 days and it is most likely that the same question was asked of vapers, but these results are not reported. Studies that assessed frequency of use report that as with non-smokers who try nicotine replacement products such as nicotine chewing gum, it is extremely rare for non-smokers who try vaping to progress to regular use. While some smokers find e-cigarette satisfactory and switch to vaping, the majority of non-smokers who experiment with e-cigarettes only try them once or twice and virtually none progress to daily use.

On 2017 Jan 25, Peter Hajek commented:

The press release claimed that ‘E-Cigarettes are Expanding Tobacco Product Use Among Youth’ but this study showed no such thing. It detected no increase in youth smoking, on the contrary, the continuous decline in smoking shows that e-cigarettes are not expanding smoking.

In fact, the data in the paper suggest that if anything, the increase in vaping has been associated with an accelerated decline in smoking. The cut-off point of 2009 seems to have been selected to show no acceleration, but very few young people tried vaping in 2009. By 2011, only 1.5% of middle and high school students vaped within the past 30 days and the figures went up after that. If the decline in smoking over 2004-2011 is compared with the decline over following years, it may well have significantly accelerated.

The final conclusion that ‘E-cigarette–only users would be unlikely to have initiated tobacco product use with cigarettes’ makes no sense because e-cigarette only users have not initiated any tobacco product use!

If the authors mean by this that they initiated nicotine use, this is unlikely. In this as in other similar reports, smokers were asked on how many days they smoked in the past 30 days and it is most likely that the same question was asked of vapers, but these results are not reported. Studies that assessed frequency of use report that as with non-smokers who try nicotine replacement products such as nicotine chewing gum, it is extremely rare for non-smokers who try vaping to progress to regular use. While some smokers find e-cigarette satisfactory and switch to vaping, the majority of non-smokers who experiment with e-cigarettes only try them once or twice and virtually none progress to daily use.

On 2017 Feb 04, Carl V Phillips commented:

None