Comparability

Comparability - geographical

For European comparable statistics in the field of substance abuse, please refer to the EUDA (European Union Drugs Agency), where the Danish Health and Medicines Authority participates and contributes data for Denmark.

Comparability over time

These statistics are calculated and comparable for the period 2015 onwards. Since there are municipalities in the statistics that have not approved their data, this means that analysis of the development over the time series should only be done for the municipalities included in all years. All 98 municipalities are included for 2021-2024, making it possible to compare these four years. For 2020 and 2019, 97 municipalities are included, for 2017, 96 municipalities are included, for 2016, 91 municipalities are included, and for 2015, 90 municipalities are included.

The statistics are foundationally comparable to previous statistics from the Danish Authority of Social Services and Housing's data banks for the Drug Abuse Database, which was closed down in 2017 in connection with task transfer from the Danish Authority of Social Services and Housing to Statistics Denmark. Due to an intensified course of contact with the municipalities from 2017 onwards, the coverage in the present statistics will probably be higher than in the previous statistics. The data base for these statistics contains data back to 1996, however, comparability seems difficult. In the Structural Reform from January 2007, when municipalities were merged, the responsibility for drug abuse treatment passed from the then counties to the municipalities.

The data basis for this statistics contains data dating back to 1996, but comparisons over time should be made with caution due to extensive structural changes along the way. On September 1, 2024, a the new regional treatment centers opened, aimed at the treatment of citizens with both a substance use disorder and a psychiatric diagnosis. Data from these regional dual diagnosis services are not included in this publication but are expected to be part of the 2026 publication. This may impact the comparability over time. According to current plans, only individuals receiving psychiatric treatment but registered with a substance use diagnosis will be included during the period from September 2025 to July 1, 2025.

Three major rounds of data reporting simplification have been carried out while Statistics Denmark has been responsible for the database:

• July 1, 2019: The entire ASI form was discontinued, and several questions were removed from the Admission, Services, and KvalHep forms.

• January 1, 2024: From this date, the Admission, Services, and Discharge forms became optional to report, and as of January 1, 2025, they were no longer be possible to report. Therefore, submissions of these forms after January 1, 2024, will be incomplete and underestimated. For that reason, the SMDB_IBIB dataset will no longer be published as micro-data.

• July 1, 2025: The entire KvalHep form will be discontinued, and a number of background variables (name, gender, citizenship, ethnic origin, education, and housing situation) will be removed or simplified.

Before the publication of 2023 data, an error occurred that resulted in an overrepresentation in the variable 'Other' across all years (2015–2023). This error has now been corrected.

After the publication of 2023 data, Statistics Denmark became aware of an error in a municipal IT system that caused the incorrect registration of no cases exceeding the treatment guarantee in some or all years from 2020 to 2023 for the municipalities of Greve, Lolland, Kerteminde, Langeland, Nordfyns, Nyborg, Odense, and Svendborg. This error has now been corrected.

Ahead of the 2024 publication, the Copenhagen municipality informed Statistics Denmark that they had mistakenly registered 2,419 enrolments by the drug type ‘Other (medical) treatment provided under §142 of the Health Act’ instead of ‘Drug-free treatment provided under §101 of the Social Services Act (or §33 of the Children’s Act)’. This error has now been corrected.

Limitations in comparability between municipalities

Statistics Denmark maintains ongoing dialogue with municipalities regarding correct data reporting. In the validation of 2024 data, we have taken a more systematic approach and have identified key challenges related to proper reporting practices in municipalities. Statistics Denmark is also working on an overview identifying which municipalities experienced issues in specific areas during the 2024 validation process.

The most significant and pressing challenge is that many municipalities are still unaware that children and adolescents under the age of 18 in substance abuse treatment must be reported to the SMDB. This issue is compounded by the fact that the responsibility for reporting individuals above and below the age of 18 is often split between two separate departments within the municipality (typically the substance abuse department and the children/family department). With the introduction of The Child Act on January 1, 2024, children and young people receiving social substance abuse treatment were given their own legal provision (§ 33), which clearly states that they must be reported. This has led to increased awareness among many municipalities. Furthermore, Statistics Denmark believes that most municipalities previously unaware of this obligation have now been informed as part of the 2024 data validation process. Trends in the data should be interpreted in light of this. The number of children and adolescents in substance abuse treatment is currently underestimated, but an increase is expected in the coming years due to improved reporting practices.

Statistics Denmark has also become aware that some municipalities register children and adolescents under 18 receiving substance abuse treatment under § 52 of the Social Services Act. These cases are included in a different dataset published by Statistics Denmark. The municipalities have been informed that this is incorrect.

During the validation of 2024 data, additional issues related to municipalities' IT systems were identified. In one IT system, it was found that users did not intuitively realize that multiple enrolments could be created in the same treatment course. However, this is possible, and both Statistics Denmark and the IT provider have provided guidance to users on how to do this. In another system, it was discovered that it was not possible to register requests without corresponding treatment initiations. This has since been corrected, retroactively for several years. Many municipalities have not been, and in some cases still are not, aware that all requests must be registered—even those not resulting in actual treatment (i.e. initiation). Statistics Denmark believes an increasing number of municipalities are becoming aware of this requirement and are reporting all requests moving forward. However, a few municipalities have indicated they only have the resources to report requests that result in treatment (initiation). In these cases, the number of requests and initiations will be identical, and the request data cannot be used to assess the gap between demand and actual treatment provision.

Statistics Denmark has also learned that some municipalities are unaware that multiple enrolments can be registered within the same treatment course. When a change in treatment provider occurs, some municipalities have ended the entire treatment course and registered a new one. This leads to an overestimation of the number of requests, initiations, and ended treatment courses. However, Statistics Denmark assesses that the vast majority of municipalities are aware of the correct practice regarding registering multiple enrolments.

In a few municipalities, only § 142 is reported when a citizen receives treatment under both § 142 (of the Health Act) and § 101 (of the Social Services Act). This reporting practice results in an underestimation of the number of individuals in § 101 treatment.

Some municipalities forget to report treatment courses that are not provided at their own municipal treatment center.

There are also municipalities that are unaware that the treatment initiation date should be the date treatment actually begins. Many instead register the assessment date. This affects the interpretation of whether treatment guarantee timelines are met. In one municipality, it was discovered that the request date and the initiation date were identical for all active cases. This presents a misleading picture of compliance with the treatment guarantee. Statistics Denmark is in dialogue with the municipality to correct these dates.

Coherence - cross domain

There is no direct connection with other statistics from Statistics Denmark.

Statistics users who are generally interested in drug abuse treatment for both drug abuse and alcohol can be referred to the National Alcohol Treatment Register (NAB) at the The Danish Health Data Authority.

Municipalities' services under Serviceloven are calculated across social statistics, i.a. adults (disability), vulnerable children and young people and drug abuse by Statistics Denmark. The sources for these statistics are often based on the municipalities' administrative IT-systems.

Coherence - internal

Data is consistent through a number of rules that ensure this. Consistency in the dataset is also ensured (see section "Forretningsregler" in the requirement specification). In some tables tables, different definitions makes the number of persons differ marginally. E.g. a person who have moved from one municipality to another can be counted more than once in SMDBV002 but not [SMDBV003](https://www.Statbank.dk/SMDBV003].