Firstly it is a US study, which always contains problems as over here, we seem to think of the USA as one massive country, where in reality, it is much more like the EU. Lots of different countries under one constitution.
If you take individual states, you will find that the more populous and cosmopolitan states are reducing smoking on a par with the UK or any other major UK or european country. The figures are skewed by the more rural states/areas, some of whom are tobacco producing areas, where smoking has not reduced and in some cases increased.
Secondly, given the US stance on drugs in certain states, how many of these devices are actually being used as "Dry Herb" vapourisers? If that was what I was using it for, and I was young and in a state with strict drug policy, I would probably claim to be vaping eliquid rather than weed.
Too easy to make these studies say what the writer wants them to say. Lies, Lies and Damned Statistics.
