Smoking habit was analysed as a dichotomous variable (non-smoker and smoker).
I agree that there are many areas in which smoking can he inhaled if one is a non-smoker.
First, the incidence of lung cancer in an industrial area shows the same discrepancy as between the non-smoker and the heavy smoker.
They will dissuade the smoker and protect the non-smoker.
I am a non-smoker and am therefore thoroughly impartial.
The smoker might live to 73, but a non-smoker or a snus user would have a life expectancy of 81.
Similarly, a non-smoker does not need nicotine, but the addict does and is miserable without it.
Conversely, if a person is a non-smoker at 20 he is likely to remain so for the rest of his life.