Occult-blood screening.
D000230:Adenocarcinoma / Q000175:diagnosis*; D000328:Adult; D003110:Colonic Neoplasms / Q000175:diagnosis*; D003111:Colonic Polyps / Q000175:diagnosis; D006801:Humans; D008875:Middle Aged; D009780:Occult Blood; D012004:Rectal Neoplasms / Q000175:diagnosis*; D012306:Risk