title: Biochemical verification of tobacco use and cessation.
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D006801:Humans; D012016:Reference Values; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012907:Smoking; D016540:Smoking Cessation; D013997:Time Factors; D014029:Tobacco Use Disorder / Q000175:diagnosis
chemical_list: D015415:Biomarkers