On average, symptoms (if they appear) develop within 1 to 3 weeks after exposure
A third draft was delivered, but it did not - and could not, given the inherent weakness of the underlying survey - address the fundamental problems raised by the reviewer: that there was misclassification bias in the data, that there was likely to be reverse causation at work, and that the smokers who switched to vapes had quit smoking, on average, more recently than the other ex-smokers
Exploratory analysis will consider intervention effects on the smoking rate, such as smoking reductions
Research indicates that exclusive current pipe smokers face elevated mortality risks compared to never tobacco users
Current occupation was categorized into three types: government employee, teacher, or healthcare provider