title: [Incidence of rheumatoid arthritis in children in relation to age and sex].
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001171:Arthritis, Juvenile / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011044:Poland; D012737:Sex Factors
vernacular_title: Zachorowalność dzieci na reumatoidalne zapalenie stawów w zalezności od wieku i płci.