Rheumatoid arthritis in both marital partners.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000453:epidemiology* / Q000235:genetics; D002648:Child; D004777:Environment; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012494:Sampling Studies; D012737:Sex Factors; D013548:Sweden