Epidemiology of Crohn's disease.
D000328:Adult; D000367:Age Factors; D002980:Climate; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology*; D004777:Environment; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D012424:Rural Population; D012737:Sex Factors; D014505:Urban Population