title: National registers and their use for medical research.
authors: Department of Clinical Epidemiology, C7-P, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands, f.r.rosendaal@lumc.nl.
authors: Frits R
authors: FR
authors: Rosendaal
mesh_terms: D035843:Biomedical Research; D019992:Databases as Topic; D003718:Denmark; D016021:Epidemiologic Studies; D006801:Humans; D012042:Registries