Finnish health and social welfare registers in epidemiological research

Finland introduced a personal identification number system in 1964, and since then practically all administrative registers have included this unique identification code. Currently Finland has strict data protection laws, which prohibit the collection of sensitive health and social information. Health data that includes identifiers can be gathered by obtaining informed consent from the patients or clients, or under special legislation. An important exemption of this general principle, however, is the collection and use of such data for statistical and scientific purposes, for example in epidemiological studies. Thus, these registers can be used as a basis when trying to improve health, welfare, health services, and social welfare services. This article describes the health and social welfare register system and data protection legislation in Finland, and gives some examples on epidemiological register studies. This article also presents methods for promoting register research, including the newly launched Finnish Information Centre for Register Research.