Sexual risk behaviors decline among high schoolers.
D000293:Adolescent; D000294:Adolescent Behavior; D000328:Adult; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D011159:Population Surveillance; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D013334:Students; D011795:Surveys and Questionnaires; D014481:United States; D014505:Urban Population