Background: Low spirometry levels in persons who are smokers have been shown to increase smoking cessation rate, while some other studies have shown that pulmonary function testing in smokers has no effects on smoking cessation. Contradictory results of few studies on this subject inspired to investigate the effect of identifying smokers with COPD or deranged physiological findings via spirometry, and its implication to smokers on the success rate of quitting smoking in the short-term interval.