From the Centers for Disease Control and Prevention. Trends in sexual risk behaviors among high school students--United States, 1991-2001.
D000293:Adolescent; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D011159:Population Surveillance; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D013334:Students / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology