Trends in cigarette smoking among high school students--United States, 1991-1999.
D000293:Adolescent; D000294:Adolescent Behavior; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012907:Smoking / Q000453:epidemiology*; D013334:Students / Q000523:psychology / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology