Statistical processing

Source data

Reports from the municipalities and drug abuse treatment centers. From January 1, 2024, it is only mandatory to report for drug abuse offers that have authorization to report on behalf of a municipality.

Frequency of data collection

Municipalities are obliged to report data on social drug addiction treatment to Statistics Denmark on an ongoing basis, however no later than 15 days after the end of the month, cf. Bekendtgørelse om dataindberetninger på socialområdet.

Municipalities are obliged to report data on medicinal drug addiction treatment to Statistics Denmark on an ongoing basis, however no later than 1 month after initiation of treatment, cf. Bekendtgørelse nr. 895 af 25. juni 2025.

Data collection

Direct reporting or system-to-system reporting via administrative IT-system to SMDB.

Data validation

As part of the data validation process, Statistics Denmark continuously monitors whether we receive data on time and whether the data appears accurate. If Statistics Denmark finds that fewer cases have been reported than expected, it contacts the municipality to clarify whether the municipality needs advice and guidance regarding reporting. If the issue is due to IT problems, Statistics Denmark will attempt to resolve them, often in collaboration with the municipality’s specialized system. Statistics Denmark has begun monitoring data from the middle of the census year, rather than first reviewing data after the census year has ended.

Statistics Denmark’s deadline for when municipalities must have reported, validated, and approved their data is communicated through an annual calendar via Statistics Denmark’s information page as well as via email to relevant contacts.

For 2025 reports, the approval deadline was February 24, 2026, which gave municipalities nearly two months to review reports for the 2025 census year and correct errors and omissions prior to approval. Following the end of the census year, Statistics Denmark is in dialogue with the reporting entities to validate and approve the data. In connection with the validation of the 2025 data, Statistics Denmark asked the municipalities, as a new measure, to log in to the SMDB web portal and validate their reports based on [6 questions](https://www.dst.dk/Site/Dst/SingleFiles/ GetArchiveFile.aspx?fi=velfaerd&fo=smdb-godkend-sporgsmal-2025--pdf&

Data compilation

After data is reported to the Substance Abuse Database, the citizen’s age at the time of the incident is calculated. However, the age listed in the StatBank is the citizen’s age at the end of the census year, not when the citizen began treatment.

Gender is retrieved from the CPR registry.

Only approved municipalities are included in the published figures.

It is only possible to report individuals with a valid CPR number. For this reason, anonymous individuals in substance abuse treatment are not reported, and likewise, foreign nationals who have not yet received a Danish CPR number cannot be reported to the Substance Abuse Database.

Previous analyses of data from the Substance Abuse Database have shown that a large proportion of the active contact cases in the database should have been closed. In connection with a municipality’s system change (i.e., switching from one specialized system to another or to manual reporting), a review of active cases is conducted so that erroneously open cases are closed before the transition to the new system.

Frederikssund Municipality (2018) and Kalundborg Municipality (2019–2020) were unable to validate their data. To calculate national totals, selected key figures have therefore been estimated through imputation based on trends in the surrounding years. The imputed values are used solely for calculating national totals and are not shown at the municipal level. The method has been tested on other municipalities and is deemed to yield satisfactory results. Further information on the imputation is provided in the methodology document Imputering 2018-2020.pdf.

Adjustment

When there are fewer than 10 days between two contact or treatment episodes for the same citizen in the same municipality, the two episodes are combined in the episode registry (SMDB_VBGF), but not in the event registry (SMDB_VBGH). This is done because we assume that contacts/courses of care with less than 10 days between them belong to the same course of care.

Previously, some municipalities implemented system changes (change in system vendor/specialized system) or transitioned to or from direct reporting by closing all open cases on a date agreed upon with Statistics Denmark and registering new courses with a request date the following day. This was corrected by marking one of the cases with a ‘system change correction variable,’ which indicates that it should not be included in the event register (SMDB_VBGH).

Statistics Denmark encourages municipalities to switch systems using a new model where system change correction is not necessary. Under the new model, all active cases in the old system are deleted and re-reported in the new system. Most system changes after 2022 have been carried out using the new model. The new model provides more accurate data, as there are no cases that need to be merged during post-processing.