zahra nikooseresht department of epidemiology & biostatistics, school of public health, tehran university of medical sciences, tehran, iran shahnaz rimaz department of epidemiology & biostatistics, school of public health, tehran university of medical sciences, tehran, iran mohsen asadi-lari department of epidemiology & biostatistics, school of public health, oncopathology research centre, tehran university of medical sciences, tehran, iran saharnaz nedjat department of epidemiology & biostatistics, school of public health, knowledge utilization research center, tehran university of medical sciences, tehran, iran effat merghati-khoee iranian national center of addiction studies (incas), institution of risk reduction, tehran, iran and department of psychiatry and behavioral sciences, medical university of south carolina (musc), usa nargess saiepour department of epidemiology & biostatistics, school of public health, tehran university of medical sciences, tehran, iran and school of public health, university of queensland, queensland, australia