Questionnaire
A descriptive questionnaire for the assessment of smoking habits among primary healthcare physicians was adapted from Al zayani [18].
The questionnaire specifically asked about cigarette smoking, waterpipe (shisha) and other forms of tobacco smoking.
Former and never cigarette smokers were defined according to the Centre for Disease Control and Prevention (CDC) guidelines [19] and underlined under each question.
Since there are no such guidelines for waterpipe smoking, we defined former waterpipe smokers as ‘used to smoke regularly at a frequency of at least once a month but have not smoked in more than one month’ and never waterpipe smokers as ‘I don’t smoke waterpipe and have never smoked waterpipe with a frequency of at least once a month or more’.
Current and former smokers were asked about age of smoking initiation as well as age of quitting for the latter.