Prevalence and associated factors of smoking in middle and high school students: a school-based cross-sectional study in Zhejiang Province, China.

OBJECTIVES To determine the prevalence and associated factors of smoking in a Chinese adolescent population. SETTING A multistage, stratified cluster sampling technique was used in the present cross-sectional study conducted in Zhejiang Province of China. Based on socioeconomic status, school levels and geographical positions, 253 middle school classes, 122 academic school classes and 115 vocational high school classes located in 12 urban areas and 18 rural areas were chosen. PARTICIPANTS A total of 9617 middle school students, 5495 academic high school students and 4430 vocational high school students were recruited in this survey. PRIMARY AND SECONDARY OUTCOME MEASURES Ever, current smoking status and associated factors were collected via a self-administered questionnaire. Logistic regression models were used to examine the associations between current smoking and the associated factors. ORs with their 95% CIs were reported. RESULTS Overall, the prevalence of ever-smokers and current smokers was 33.83% and 7.93%, respectively. Focused on current smokers, significantly higher risks of adolescent smoking were observed in an older age group, boys, rural areas and vocational high school. Other significant factors were parents smoking, secondhand smoke exposure, parental divorce or separation, living with family, school performance and belief that smoking is harmful. CONCLUSIONS The prevalence of smoking was relatively high among Chinese adolescents in Zhejiang Province. Factors related to personal characteristics, family and school were associated with adolescent smoking.