Accuracy and reliability

Overall accuracy

The Central Population Register (CPR) is an administrative register with a very wide scope of application. The quality of the information is usually very high.

Sampling error

Not relevant for these statistics.

Non-sampling error

A source of unreliability is the group of persons without permanent addresses. They are registered at certain special municipal addresses which are of a fictitious nature and which are administered by the local population registers. They are reserved for persons who, for one reason or another, cannot be registered at a permanent address. They include homeless people, seamen, posted diplomats and certain other groups of people working abroad for Danish authorities or organizations.

A second source of unreliability is institutional households (e.g. old-age nursing homes) whose residents are often registered at individual addresses. A great number of residents living at assisted living facilities, which in reality are like nursing homes, are registered as living in their own one person household.

Finally, statistical uncertainty is derived from missing references to parents. References to parents are coupled to almost everyone born after 1960, while they are missing for almost everyone born before 1950.

No reliable estimate is available concerning the scale of incorrect and missing addresses.

Quality management

Statistics Denmark follows the recommendations on organisation and management of quality given in the Code of Practice for European Statistics (CoP) and the implementation guidelines given in the Quality Assurance Framework of the European Statistical System (QAF). A Working Group on Quality and a central quality assurance function have been established to continuously carry through control of products and processes.

Quality assurance

Statistics Denmark follows the principles in the Code of Practice for European Statistics (CoP) and uses the Quality Assurance Framework of the European Statistical System (QAF) for the implementation of the principles. This involves continuous decentralized and central control of products and processes based on documentation following international standards. The central quality assurance function reports to the Working Group on Quality. Reports include suggestions for improvement that are assessed, decided and subsequently implemented.

Quality assessment

The statistics are based on the Central Population Register (CPR). The information in CPR is considered to be of very high quality.

It is very important for the primary data of the statistics that the address information is reliable. The statistics are influenced by the extent to which the population is not registered in the CPR register at real addresses. No estimates are made of the scale of this problem, and it is not possible to make corrections for this

Data revision - policy

Statistics Denmark revises published figures in accordance with the Revision Policy for Statistics Denmark. The common procedures and principles of the Revision Policy are for some statistics supplemented by a specific revision practice.

Data revision practice

Not relevant for these statistics.