Exposure to anti-smoking campaign
0 = No exposure
10 = Maximum exposure

Smoking status
0 = Non-smoker
1 = Smoker

Smoking status
0 = Non-smoker
1 = Former smoker
2 = Smoker

Contact with smokers
0 = No contact
10 = Maximum contact

-5 = Very negative
0 = Neutral
5 = Very positive