About the Xchange prevention registry


Xchange is an online registry of evidence-based prevention programmes. In its first phase, the registry made available manualised interventions for which good European evaluation studies showed beneficial outcomes relating to substance use. Now it also contains programmes for deliquency and violence prevention in youth. For programmes of US origin, the registry also provides the evidence ratings based on evaluation studies at a global level (Blueprint ratings).

The initial research for eligible prevention programmes and the rating process was done within the project: “Communities That Care (CTC) European Network: Making CTC work at the European level” (1/2013 – 12/2015), supported by the “Prevention of and Fight against Crime Programme” (European Commission - Directorate General Home Affairs).

In addition to providing information on the effectiveness of programmes, the registry also offers information on the experiences of professionals who have implemented these programmes in individual European countries. This enables decision-makers to assess the ease with which programmes can be implemented in different social, cultural and organisational contexts.

The registry is the centrepiece of a growing network of national registries. Through Xchange, an interested visitor can access additional details on a specific programme in the national language within a local registry, or access through a national registry the European implementation experiences of a given programme.

What is the scope of the registry and what kind of programmes are included?

At present, Xchange contains 38 manualised prevention programmes, all of which address substance use-related problems and now also delinquency and violence (11 additions in 2018). In order to join the registry, a programme must be still active or able to be used in Europe (i.e. programme manual and materials are avaliable) and have a scientifically sound outcome evaluation in at least one European country, without iatrogenic effects. In future, Xchange will be expanded to include programmes that target other risky behaviours and environmental interventions at local level.

Why such a European registry?

The Council of the EU’s Minimum quality standards in drug demand reduction in the EU demands that prevention professionals have access to knowledge on effective prevention programmes. A growing number of programmes are considered effective at reducing substance use and related problems under carefully controlled conditions. However, access to evidence‐based prevention programmes is still limited and they remain under‐utilised compared to prevention strategies with no empirical evidence for effectiveness. Xchange aims to address this challenge by providing access to such programmes.

An additional challenge is that, even when effective programmes are used, they are not being implemented with quality and fidelity in real-life settings, often because they do not fit into the existing prevention culture and infrastructure. Xchange provides decisional support by continuously compiling information on implementation experiences with the programmes contained within it.

Users can access information on the effectiveness of a programme and on the extent to which it can be implemented. The real-life scenario in Europe’s multiple cultures is that a highly effective programme may not be easy to implement in a given country, while a less effective programme may be easier to implement. Users of Xchange will have more tools for balanced decision-making at their fingertips because the registry also allows for selecting programmes according to targeted outcomes or the risk and protective factors it addresses.

A unique feature of Xchange is that it allows national high-ranking programmes to be promoted in this European registry and, inversely, allows international visitors to find more details about local adaptations in national languages. If you would like to share your experience of implementing one of the programmes in the registry, you are invited to contribute by filling in the online implementation questionnaire (https://drugusersurvey.limequery.com/index.php/839193/lang-en).

How does a programme get into our registry and how do we get to the rating?

If you would like to submit your programme to the Xchange registry, please fill in our Proposal for Inclusion Form and send it to evidence-Xchange@emcdda.europa.eu.

Xchange mandatory inclusion criteria:

  1. Focus of the intervention: Does the intervention target substance-related/violence/delinquency outcomes?
  2. Is the intervention still active or able to be used in Europe?
  3. Is the intervention clearly defined (outcomes, target group, risk and protective factors, logic model or theoretical rationale)?
  4. Is there at least one suitable evaluation study in Europe (RCT, Quasi-experimental design or interrupted time series) for this intervention?
  5. Are the expected outcomes measured?

The next step is to fill in the TIDieR Checklist (Template for Intervention Description and Replication) and provide us with additional information on implementation and dissemination of intervention.

Then, the rating procedure follows this protocol - Xchange - Inclusion and Rating Protocol (download for more information).

About Xchange ratings

More information on the ratings used are provided below.

Beneficial: Interventions for which convincing, consistent and sustained effects for relevant outcomes are in favour of the intervention as found in two or more studies of excellent quality in Europe.

Likely to be beneficial: Interventions for which convincing and consistent effects for relevant outcomes are in favour of the intervention as found in at least one evaluation study of excellent quality in Europe.

Possibly beneficial: Interventions for which some effects for relevant outcomes are in favour of the intervention as found in at least one evaluation study of acceptable quality in Europe. An intervention ranked as ‘possibly benifical’ is suitable for application in the context of more rigourous evaluations.

Additional studies recommended: Interventions for which concerns about evaluation quality or consistency of outcomes in Europe make it difficult to assess if they are effective or not, even if outcomes seem to be in favour of the intervention.

Unlikely to be beneficial: Interventions for which at least one evaluation of excellent quality in Europe shows convincing evidence of no or harmful effects on relevant outcomes.

Why can I not find a programme that I know or have heard of?

There are a number of possible reasons for this, including:

  • It has not been entered yet into the registry. The REITOX National Focal Points and the network of the EUSPR are looking for eligible programmes and we are also aiming at including more programmes from national registries of evidence-based programmes in Europe, if they fulfil the entry criteria of Xchange
  • The studies in Europe related to the programme do not fulfil the criteria above. If the quality of the studies in Europe - even of well-known programmes - is not satisfactory, these programme don't appear in Xchange, even though they might be listed in International Registries.

What if I don’t agree with the evidence rating of a programme?

The registry is dynamic and constantly evolving: if you disagree with an evidence rating or are aware of new good quality studies which review the behavioural outcomes of any of the programmes included in Xchange, please send them to evidence-Xchange@emcdda.europa.eu

These will be discussed at the next meeting of the Review Board of the Xchange registry and will be taken into account when rating the evidence of the respective entry. The board currently consists of one member of the EMCDDA Scientific Committee, members of the European Society for Prevention Research, EMCDDA staff members and appointed experts. The list of current members can be found on the Xchange partners page

What next?

The registry will be expanded to address an increasing range of solution-oriented interventions (e.g. local environmental strategies, non manualised prevention principles; and later prevention of radicalisation).


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