The epidemiology of polymyositis.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003882:Dermatomyositis / Q000453:epidemiology; D004812:Epidemiologic Methods; D005006:Ethnicity; D005260:Female; D005843:Geography; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009135:Muscular Diseases / Q000453:epidemiology; D009220:Myositis / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D012737:Sex Factors; D012959:Socioeconomic Factors; D013714:Tennessee