Scope of health education.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D006266:Health Education / Q000639:trends*; D006293:Health Promotion / Q000639:trends; D006801:Humans; D008875:Middle Aged; D011322:Primary Prevention / Q000639:trends; D014481:United States