Accuracy and reliability
Contact info
Labour Market, Social StatisticsMikkel Zimmermann
+45 51 44 98 37
Get as PDF
The statistics are based on reports from Central Employee Organisations and other employee organisations. Not all employee unions are able to calculate the precise figures exclusive members not attached to the labor market, i.e.. students, early retirees and pensioners, and self-employed. The data are therefore believed to be a little overestimated for some organisations. On the other hand, there may be small employee organisations that are not included. The data are normally not revised, but if errors are detected they are corrected back in time as far as possible. Although participation in the statistics is voluntary, all employee organisations appear to submit data.
Overall accuracy
The reported data are however assumed to be a little overvalued for some organisations. This is based on our experience which shows that not all employee organisations are able to estimate the figures excluding members not attached to the labour market. In other words, students, early retirees and pensioners, as well as self-employed may be included . Besides that there is a little risk that new small employee organisations have not been included in the population.
Sampling error
The statistics are based on an approximated census.
Non-sampling error
The frame population consists of 100 to 110 Danish employee organisations, with slight annual variation. Measurement errors may occur if some organisations are unable to clearly distinguish members with labour market attachment. Both over- and under-coverage occur. Employees who are members of more than one organisation are counted more than once. There is no known non-response, and no model-based assumptions are applied.
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
A questionnaire is sent to those employee organisations which it have been identifiable. Not all organisations are able to determine the figures exclusive members not attached to the labour market, i.e. there may be trainees, retirees and early retirees included in the figures as well as self-employed. To the extent that organisations are able to correct errors previously reported, the figures are corrected to the extent that it is possible, however this is often difficult for historic data. No figures are available regarding the size of insecurity. Quality is assessed to be reasonable.
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
Normally the published figures are not revised. If errors are detected in the published figures, these will, however, be corrected. For example, the total number of members with labour market affiliation as of 31 December 2023 was revised upwards by 3,441 members of HK in connection with the publication of the statistics as of 31 December 2024 on 19 May 2025.