前言
工作場域對戒菸行為非常地重要，因為這是大部分成人花最多時間的地方。工作場域不只是個可以舉辦戒菸活動的場所；更重要的，它所帶來的組織和社交環境是可以影響到戒菸行為的，例如禁菸政策的落實、或是為在工作上共事的吸菸者提供一個有利於戒菸行為的社交氛圍。
本研究欲探討同事的吸菸狀態會否影響吸菸者會否戒菸。

研究方法
本研究使用某鋼鐵工廠2007-2010年的員工健康檢查資料將1,423位未曾於2007年之前、或開始於該工廠工作前戒過菸的吸菸者納入觀察，並且連結工廠的管理資訊以及2012年健康檢查問卷建立吸菸者的研究變項，包括：吸菸狀態、有否戒菸、婚姻狀態、教育程度、個人健康史。本研究也將吸菸者編入工作單位，並且為每位吸菸者算出每年同單位吸菸、戒菸比例，以時間相依共變項之存活分析(time-dependent survival analysis)來探討吸菸者會否戒菸。

研究結果
戒菸者較吸菸者年紀大、更多已婚或同居、教育程度較高、任職於管理階級、年資較長。同單位內仍吸菸者、已戒菸者和同年戒菸者的比例對吸菸者會否戒菸沒有顯著的影響。

討論
本研究並未找出同單位內仍吸菸者、已戒菸者和同年戒菸者的比例對吸菸者會否戒菸顯著的影響。可能的解釋包括全國性的禁菸政策、樣本數太小、工作單位編制未反映出員工之間的社交互動、遺漏資訊，以及測量方式不夠精準。

Introduction
The workplace is important to smoking cessation because most adults spend the most of their waking time there. While the workplace can be a venue for cessation-related activities and programs, it more importantly fosters an organizational and social environment that may influence quitting, such as implementing and reinforcing smoking bans, as well as establishing social norms conducive to smoking cessation amongst individuals who work together.
This study investigates the effect of co-workers’ smoking status on whether a smoking employee would quit smoking.

Methods
Using data from the employee health examination records of a steel company for the years 2007-2010, 1,423 ever-smokers without any prior smoking cessation before 2007 or employment start date were identified and included as study subjects. By linking their data to a supplementary survey of the 2012 employee health examination and management records, variables were created for smoking status, smoking cessation, marital status and educational attainment, health history, and job-related characteristics. Work-unit groups were assigned, and proportions of co-workers who were current-smokers, quitters or new quitters in the work-unit were computed, which were further analyzed with time-dependent survival analysis using smoking cessation as the event of interest.

Results
Compared to current smokers, quitters are older, more likely to be married or partnered, obtained higher educational level, in managerial positions and with longer employment. The proportion of co-workers who are current smokers, who have quit smoking any time and who have recently quit in the same work-unit was found to have no significant effect on smoking cessation.

Discussion
Co-worker smoking rate, quit rate and newly quit rate were not found to have significant effect on smoking cessation in this study. Possible explanations include the national anti-smoking policy, small sample size, work-unit grouping not relevant to social interaction of the employees, the amount of missing data, and the lack of precise definition in this study.

Allison, Paul D. 2010. Survival Analysis Using SAS®: A Practical Guide, Second Edition. Cary, NC: SAS Institute Inc.
Bandura, A., 1986. Social Foundations of Thought and Action. A Social Cognitive Theory. Prentice Hall, Englewood Cliffs, NJ.
Chen, F.-L., et al., The role of betel-quid chewing in smoking cessation among workers in Taiwan. BMC public health, 2014. 14(1): p.755.
Christakis, N.A. and J. H. Fowler, The collective dynamics of smoking in a large social network. New England Journal of Medicine, 2008. 358(21):p.2249-2258.
Derby, C.A., et al. Characteristics of smokers who attempt to quit and of those who recently succeeded. American journal of preventive medicine, 1994.
Dijkstra, A., & J. Brosschot. Worry about health in smoking behavior change. Behaviour Research and Therapy, 2003. 41:1081-1092.
Fernández, E., et al., Social class, education, and smoking cessation: long-term follow-up of patients treated at a smoking cessation unit. Nicotine & Tobacco Research, 2006. 8(1) p. 29-36.
Fujishiro, K., et al., Occupational gradients in smoking behavior and exposure to workplace environmental tobacco smoke: the multi-ethnic study of atherosclerosis. J Occup Environ Med, 2012. 54(2): p. 136-45.
Helliwell, J.F. and R.D. Putnam, The social context of well-being. Philosophical transactions-royal society of London series B biological sciences, 2004: p.1435-1446.
Honjo, K., et al. What accounts for the relationship between social class and smoking cessation? Results of a path analysis. Social science & medicine, 2006. 62(2):p 317-328.
Health Promotion Administration, M.o.H.a.W.衛., 2013 Taiwan Tobacco Control Annual Report (2013臺灣菸害防制年報). 2014.
Health Promotion Administration, M.o.H.a.W.衛., 健康數字123 Plus:國民健康指標互動查詢網站.
Japuntich, S.J., et al., Smoker Characteristics and Smoking-Cessation Milestones. American Journal of Preventive Medicine, 2011. 40(3):p. 286-294.
Kawachi, I., et al. Commentary: Reconciling the three accounts of social capital. International Journal of Epidemiology, 2004. 33(4): p.682-690.
Kouvonen, A., et al. Implementation of workplace-based smoking cessation support activities and smoking cessation among employees: the finnish public sector study. American Journal of Public Health, 2012. 102(7):p. e56-e62.
Kotz, D. and R. West, Explaining the social gradient in smoking cessation: it’s not in the trying, but in the succeeding. Tobacco Control, 2009. 18(1): p. 43-46.
Leed, C.W. and J. Kahende, Factors associated with successful smoking cessation in the United States, 2000. American Journal of Public Health, 2007. 97(8): p.1503.
Marti, J., Successful smoking cessation and duration of abstinence—an analysis of socioeconomic determinants. Int J Environ Res Public Health, 2010. 7(7):p.2789-99.
Newsom, J. T. et al., Health Behavior Change Following Chronic Illness in Middle and Later Life. The Journals of Gerontology, Series B: Psychological Sciences and Social Sciences, 2012. 67(3):p.279-288.
Nishiura et al., The Effect of Smoking Prevalence at Worksites on Individual Cessation Behavior. Journal of Occupational Health, 2009. 51:48-56.
Sherriff, N. and L. Coleman, Understanding the needs of smokers who work as routine and manual workers on building sites: Results from a qualitative study on workplace smoking cessation. Public health, 2013. 127(2): p. 125-133.
Stanton, C.A., et al., Trends in tobacco use among US adultswith chronic health conditions: National Survey on Drug Use and Health 2005–2013, Prev. Med. (2016), http://dx.doi.org/10.1016/j.ypmed.2016.04.008
Stolz, D. et al., Predictors of Success for Smoking Cessation at the Workplace: A Longitudinal Study. Clinical Investigations, 2014. 87:18-25.
Tanihara, S., and Y. Momose, Reasons for smoking cessation attempts among Japanese male smokers vary by nicotine dependence level: a cross-sectional study after the 2010 tobacco tax increase. BMJ Open, 2015;5:e006658.
Tsai, A.C., Y.A. Lin, and H.J. Tsai, Predictors of a smoking cessation in 50-66-year-old male Taiwanese smokers: a 7-year national cohort study. Arch Gerontol Geriatr, 2012. 55(2): p.295-300.
Quist, H.G. et al., Do colleagues influence our lifestyle: The matter of smoking, body mass index and leisure-time physical activity? Preventive Medicine, 2014. 67:166-170.
Wang, H.L., J. Harrell, and S. Funk, Factors associated with smoking cessation among male adults with coronary heart disease in Taiwan. Journal of Nursing Research, 2008. 16(1): p. 55-64.
Wang, K.-Y., et al., Predictors of cigarette smoking behavior among military university students in Taiwan. Journal of Nursing Research, 2009. 17(3): p.161-169.