Bicycle safety.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001265:Athletic Injuries / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D001642:Bicycling; D002648:Child; D002675:Child, Preschool; D006259:Craniocerebral Trauma / Q000453:epidemiology / Q000517:prevention & control*; D005260:Female; D006260:Head Protective Devices; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011482:Protective Devices; D013177:Sports; D014481:United States