Prevalence of rheumatoid arthritis in densely and thinly populated areas in Sweden.
D000367:Age Factors; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000453:epidemiology*; D002980:Climate; D006801:Humans; D008403:Mass Screening; D009790:Occupations; D011156:Population Density; D012737:Sex Factors; D012924:Social Conditions; D013548:Sweden