trend of smoking among students of tehran university of medical sciences: results from four consecutive surveys from 2006 to 2009

background: smoking within students community of the medical sciences can negatively impact the attitudes of the society in future. the objectives of this study were to assess the prevalence and trends of smoking among students of tehran university of medical sciences. method: this study was conducted in four consecutive years from 2006 to 2009. the study sample was taken from the first- to fourth-year, undergraduate and graduate (doctorate) students of tehran university of medical sciences. census was applied for sampling. structured questionnaires were distributed to students of each class. the study was anonymous and self-administered. results: from 2006 to 2009, a total of 1568 to 1761 students participated in the study each year. over the study period, i.e. 2006-2009, the prevalence of cigarette smoking was decreased (the overall prevalence was 12.5% in 2006, 12.9% in 2007, 10.8% in 2008, and 10.5% in 2009). the corresponding values for the one month prevalence were 8.2%, 7.8%, 6.1%, and 5.8%, while those for the prevalence of daily smoking were 3.4%, 4.0%, 2.9%, and 1.8%, respectively. the decreasing trend was particularly more significant for female students. conclusion: the findings suggest that the prevalence of smoking among students of tehran university of medical sciences was in the lower end of the spectrum, in comparison to other universities in iran and other countries. additionally, similar to the pattern observed in the developed world, this trend was decreasing, particularly among girls. implementing preventive measures for accelerating the decreasing trend, as well as continuous monitoring is recommended.