All study participants were asked about their present smoking status ("Do you currently smoke?").
Cigarette smoking was assessed by questionnaire, which included details about past and present smoking habits, number of cigarettes smoked per day and smoking duration.
Normally smoking behaviour would not change in the short term, but considering the students smoking is absolutely prohibited in Chinese schools and by most of their parents, it is understandable that the present smoking frequency of students who smoked may differ in terms of the different possibility to access cigarettes and smoke them.
Cigarette smoking was assessed by questionnaire, which included details about past and present smoking habits, the number of cigarettes smoked per day and the smoking duration.
Cigarette smoking was assessed by questionnaire, which included details about past and present smoking habits, the number of cigarettes smoked per day and the number of years the patient had been a smoker.
The following clinical information was available during the re-evaluation process: age, gender, previous myocardial infarction, previous re-vascularisation, present smoking, presence of hypertension, hyperlipidemia, diabetes, peripheral vascular disease, positive family history, and presence of typical chest pain.
Before inclusion, they all underwent a medical examination to screen for other cardiovascular risk factors: past or present smoking, hypertension (≥140/90 mmHg), LDL, HDL, and triglyceride [TG] levels, and family history of early CHD.
Past and present smoking decreased.
We used present smoking as a factor for the effect of smoking on the airways.
To dichotomize the variable, those who reported no present smoking will be considered as non-smokers.
To dichotomise the variable, those who reported no present smoking habits were considered as non-smokers.
