title: Childish habit.
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D049673:History, 20th Century; D006801:Humans; D010819:Physician's Role; D010817:Physician-Patient Relations; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology / Q000266:history; D000074606:Smoking Prevention; D014481:United States / Q000453:epidemiology