Cigarette smoking is a common habit that has detrimental effects on physical health including an increased risk of heart disease, cancer, stroke, and chronic lung disease. In the United States, cigarette smoking is the leading cause of morbidity and mortality; accounting for 30% of all cancer deaths and 80% of deaths from chronic obstructive pulmonary disease [1]. Although tobacco smoking is a complex multidimensional behavior, research has highlighted smoking quantity, usually evaluated by cigarettes per day (CPD), as a predictor of nicotine dependence [2].
