title: Registers of the Swedish total population and their use in medical research.
abstract: The primary aim of the Swedish national population registration system is to obtain data that (1) reflect the composition, relationship and identities of the Swedish population and (2) can be used as the basis for correct decisions and measures by government and other regulatory authorities. For this purpose, Sweden has established two population registers: (1) The Population Register, maintained by the Swedish National Tax Agency ("Folkbokföringsregistret"); and (2) The Total Population Register (TPR) maintained by the government agency Statistics Sweden ("Registret över totalbefolkningen"). The registers contain data on life events including birth, death, name change, marital status, family relationships and migration within Sweden as well as to and from other countries. Updates are transmitted daily from the Tax Agency to the TPR. In this paper we describe the two population registers and analyse their strengths and weaknesses. Virtually 100 % of births and deaths, 95 % of immigrations and 91 % of emigrations are reported to the Population Registers within 30 days and with a higher proportion over time. The over-coverage of the TPR, which is primarily due to underreported emigration data, has been estimated at up to 0.5 % of the Swedish population. Through the personal identity number, assigned to all residents staying at least 1 year in Sweden, data from the TPR can be used for medical research purposes, including family design studies since each individual can be linked to his or her parents, siblings and offspring. The TPR also allows for identification of general population controls, participants in cohort studies, as well as calculation of follow-up time.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17177, Stockholm, Sweden. jonasludvigsson@yahoo.com.|Department of Paediatrics, Örebro University Hospital, Örebro, Sweden. jonasludvigsson@yahoo.com.|Division of Epidemiology and Public Health, School of Medicine, University of Nottingham, Nottingham, UK. jonasludvigsson@yahoo.com.
authors.forename: Jonas F
authors.initials: JF
authors.lastname: Ludvigsson
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17177, Stockholm, Sweden.|Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Catarina
authors.initials: C
authors.lastname: Almqvist
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.|Department of Women's and Children's Health, Karolinska Institutet and Hospital, Stockholm, Sweden.
authors.forename: Anna-Karin Edstedt
authors.initials: AK
authors.lastname: Bonamy
authors.affiliation: Unit of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Rickard
authors.initials: R
authors.lastname: Ljung
authors.affiliation: Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Karl
authors.initials: K
authors.lastname: Michaëlsson
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Martin
authors.initials: M
authors.lastname: Neovius
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.|Department of Women's and Children's Health, Karolinska Institutet and Hospital, Stockholm, Sweden.
authors.forename: Olof
authors.initials: O
authors.lastname: Stephansson
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17177, Stockholm, Sweden.
authors.forename: Weimin
authors.initials: W
authors.lastname: Ye
mesh_terms: D017677:Age Distribution; D035843:Biomedical Research; D057286:Electronic Health Records / Q000941:ethics; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D032984:Ethics, Research; D005260:Female; D006801:Humans; D008297:Male; D009026:Mortality; D010355:Patient Identification Systems; D012042:Registries; D017678:Sex Distribution; D035781:Siblings; D012959:Socioeconomic Factors; D013548:Sweden / Q000453:epidemiology
keywords: Population; Public health; Register; Registry