title: [Demographic factors affect the occurrence of severe mental retardation. Is intermarriage a factor of significance also in Sweden?].
authors.affiliation: Barnkliniken, Huddinge sjukhus.
authors.forename: E
authors.initials: E
authors.lastname: Fernell
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003241:Consanguinity; D003710:Demography; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology* / Q000235:genetics; D008297:Male; D015995:Prevalence; D013548:Sweden / Q000453:epidemiology / Q000208:ethnology