In this blog article, Charlotte De Kock, researcher at Ghent University (Belgium) and member of the Xchange Prevention Registry is presenting the story of this unique European registry of evidence-based prevention interventions.
It’s been two years now since I’m involved in the development and maintenance of the Xchange prevention registry. This experience enabled me to work with a team of people who have decades of experience and expertise in drug prevention. But what is the Xchange prevention registry exactly, and what did we realise in these last couple of years?
What is Xchange?
The European Xchange Prevention Registry was officially established in 2017. Xchange is an online registry of European, evidence-based prevention interventions. It is updated approximately twice a year with new programmes and feedback from implementers (schools, public health institutes, etc.). The registry includes interventions for which good European evaluation studies showed beneficial outcomes relating to substance use, as well as programmes for delinquency 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 idea to create a European registry of evidence-based prevention interventions arose as a collaboration between EUSPR members (among others Nick Axford and Fabrizio Faggiano), who have conducted high quality reviews of such interventions (for example, the review in the framework of the European Communities That Care (CTC) project), and proactive action from EMCDDA (European Monitoring Centre for Drugs and Drug Addiction, Gregor Burkhart, Klaudia Kepa, Marica Ferri). This fruitful collaboration is a win-win to both EMCDDA and EUSPR: EMCDDA pioneered in the creation of the Xchange intervention database with the input of EUSPR experts and EMCDDA in turn supports EUSPR – both content-wise and organisation-wise – in organising the yearly EUSPR conference (which is held at EMCDDA in Lisbon every two years).
Ratings in the Xchange registry are solely based on European evaluation studies. The rationale is that interventions that have been evaluated in non-EU countries such as the United States might not easily be transferrable to a European context. Subsequently, it was necessary to build a European evidence register that enables and supports the implementation of evidence-based and informed interventions in European social and cultural contexts.
Getting on board
In March 2018, the Xchange Board launched a call to get an early career researcher on board. At the time, I was rounding up the SOCPREV project (on social prevention of drug related crime, coordinated by Freya Vander Laenen and Lieven Pauwels). During this project, we gathered European evidence on interventions aimed at reducing drug related crime in Europe. While conducting this review I got to know the CTC Europe project and contacted some of the involved researchers, practitioners, and policy makers (e.g. Frederick Groeger-Roth).
During this research project it became ever clearer that a national register of evidence-based interventions was a prerequisite for implementing interventions that work as well as for efficient policy making. That’s why I was happy to respond to the call launched by the EMCDDA/EUSPR to join the Xchange Board and to be part of this innovative project.
How does Xchange work?
In the beginning in 2018, the main workload of the Board consisted of optimising the Xchange procedure of gathering, selecting and rating interventions and intervention studies. The development of protocols enabled the Board to work more efficiently in 2019: EMCDDA (Gregor Burkhart, Klaudia Kepa) gathers studies via the Reitox National Focal Points, the EUSPR networks and other partners. The independent board members (Nick Axford, Gregor Burkhart, Catherine Comiskey, Charlotte De Kock, Fabrizio Faggiano, Marica Ferri, Johanna Gripenberg, Ina Koning) in turn rate the selected evaluation studies. The 2020 agenda is mainly focussed on how to include environmental prevention strategies as well as rating new European evaluation studies.
At present the Xchange Board rates projects into five categories presented 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 beneficial’ is suitable for application in the context of more rigorous 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

From left to right: Ina Koning, Klaudia Kepa, Catherine Comiskey, Nick Axford, Fabrizio Faggiano, Johanna Gripenberg, Gregor Burkhart, Charlotte De Kock
The Xchange board meets once a year at EMCDDA in Lisbon. The main agenda of this meeting is to agree on how to rate eligible intervention evaluation studies. A selection and rating protocol was developed for this purpose. Being a Board member is quite an interesting job really because it allows to in-depth analyse evaluation models and methods (e.g. randomized controlled trials, quasi experimental designs etc.). Additionally, it allows – at an analytical level – to ponder about which types of methods are best suited for specific interventions (e.g. the difficulty of evaluating environmental prevention interventions). It has been and still is a motivating challenge that I’ve been very glad to take up as a volunteer while conducting my day-to-day-research activities (e.g., investigating the associations between ethnicity and substance use and treatment accessibility in the projects PADUMI, MATREMI, SOCPREV, ACCESS).
It’s been great so far to meet like-minded colleagues and to be able to help translate a research recommendation in the SOCPREV project – the creation of an evidence-based prevention registry – to a real life environment. Although Xchange operates at the European level, the team keeps contact with policy makers and practitioners on the ground in the European member states. A first coordination meeting between representatives of these registries in different member states was organised during the EUSPR conference in 2019. The meeting allowed us to get acquainted with the varying registry initiatives across the member states and to support closer collaboration between these professionals. This collaboration allowed the participants to discuss issues concerning transferability of interventions, benchmarking etc.
I’m thrilled that EMCDDA has initiated and sustains the Xchange registry and that EUSPR members have taken up the task to support the Xchange registry by means of their indispensable expertise. It is inspiring to be part of this team. Xchange embodies and enables a very promising European collaboration for better, evidence-based and evidence-informed drug and crime prevention across the member states as well as more efficient fund allocation and informed policy making.

From left to right: Ina Koning, Catherine Comiskey, Fabrizio Faggiano, Johanna Gripenberg, Nick Axford, Charlotte De Kock, Gregor Burkhart (Foto: Klaudia Kepa)
About the author:
Charlotte De Kock is a researcher and co-chair of the Diversity Board at the Faculty of Law & Criminology at Ghent University, Belgium. She conducted several research projects for the Belgian Science Policy Office as the lead researcher including ‘Mapping and enhancing substance use treatment for migrants and ethnic minorities’ (MATREMI, Belspo, 2019), ‘Social prevention of drug related crime’ (SOCPREV, Belspo, 2018) and ‘Patterns of substance use among migrants and ethnic minorities’ (PADUMI, Belspo, 2015-2017). After a decade of policy oriented research work and support in education (Ghent University College 2010-2014, Ghent University 2015-now) Charlotte now studies the accessibility of substance use treatment for migrants and ethnic minorities with a PhD grant funded by the Ghent University Research Fund (ACCESS, 2019-2022). Charlotte is on the Xchange prevention registry Board (EMCDDA) since 2018.
Thank you Charlotte, a very informative article!