2025 OHDSI Europe Symposium

We are proud to announce that Hasselt University, through its Biomedical Data Sciences research group, and as co-chair of OHDSI Belgium, has been invited to host the 2025 OHDSI Europe Symposium, marking a historic moment as this prestigious event ventures beyond its traditional home in Rotterdam for the very first time. Taking place from July 5-7, 2025, the symposium will be held at the iconic Old Prison building of Hasselt University, providing a unique blend of historic ambiance and cutting-edge innovation.

This year’s symposium promises to bring together over 300 attendees, including researchers, data scientists, healthcare professionals, and policymakers, for an exceptional opportunity to connect, learn, and contribute to the growing OHDSI Europe community.

What awaits you:

• Pre-Symposium Tutorials & Workshops: Dive into a 2-day program designed for all expertise levels, offering hands-on training on OHDSI tools, ETL processes, and conducting network studies.
• Networking Opportunities: Engage with international experts and stakeholders at the forefront of health data innovation.
• Main Symposium: A scientific program developed in collaboration with Peter Rijnbeek and Patrick Ryan, continuing the tradition of high-quality content seen in previous editions.

As co-chair of OHDSI Belgium, the Biomedical Data Sciences research group at Hasselt University is delighted to welcome you to this extraordinary event. Whether you’re a newcomer or an experienced member of the OHDSI community, this symposium is your opportunity to shape the future of health data science.

We look forward to welcoming you to Belgium for this exceptional gathering!

Real-world evidence is transforming healthcare research in Europe, especially as the upcoming European Health Data Space (EHDS) legislation paves the way for secure, interoperable, and trusted cross-border data sharing. The 6th European OHDSI Symposium – Join the Network: Advancing Real-World Evidence in Europe – will take place on July 7, 2025, in Hasselt, Belgium, bringing together researchers, policymakers, and industry leaders to explore the latest developments in OMOP-CDM, open-source tools, and collaborative projects that harness the power of networks to generate impactful evidence.

This symposium is a premier platform to connect, collaborate, and share insights on advancing real-world evidence in Europe. Attendees will gain valuable perspectives on National Nodes, large-scale European projects, and other groundbreaking initiatives shaping the future of health data research. The event will feature an engaging collaborator showcase, including posters, podium presentations, and interactive demonstrations of OHDSI’s open-source tools, highlighting the power of community-driven research.

To further strengthen the network, the pre-symposium workshops and tutorials on July 5-6 offer hands-on learning, in-depth discussions, and one-on-one expert sessions—ideal for both newcomers and experienced OHDSI members looking to deepen their engagement.

Join us at the historic Old Prison in Hasselt for this pivotal event, and be part of the journey toward a more connected and data-driven future in healthcare research!

The registration fee for the 6th European OHDSI Symposium is €195 (regular) or €65 for PhD students. Your ticket includes access to the main symposium on July 7 as well as the pre-symposium workshops and workgroup meetings on July 5-6, at no additional cost.

Please note: Only registered symposium attendees can participate in the pre-symposium workshops.

🔹 Limited spots available! We have 350 places for the symposium and 150 places for the workshops and workgroup meetings. Registration closes on June 16, 2025 (23:59 CEST), or earlier if tickets sell out.

🔹 Need to cancel? If you can no longer attend, please inform us by June 5, 2025, so we can offer your spot to someone on the waiting list.

👉 Please follow this link to book your space and register for the event.

Secure your place now and join us in advancing real-world evidence in Europe!

The two days leading up to the 6th European OHDSI Symposium will feature interactive workshops, tutorials, and networking opportunities designed for both newcomers and experienced OHDSI community members.

🔹 Newcomers Track

Ideal for those new to OHDSI, this track includes an Introduction to OHDSI tutorial covering its history, philosophy, tools, and how to get started. Additional sessions will provide a "Whirlwind to open source analytic tools" introduction and an ETL (Extract, Transform, Load) tutorial, guiding data holders through the first steps of mapping their data to the OMOP CDM.

🔹 Advanced OHDSI Track

For experienced OHDSI members, this track features a Phenotyping & Vocabulary Workshop, covering key aspects of OHDSI vocabularies for phenotyping and standardized characterization studies. Participants will also explore how to conduct ‘off-the-shelf’ characterization studies using DARWIN EU® tools and the OMOP CDM.

🔹 Additional Activities

Next to the structured tracks, attendees can join data partner lunches, OHDSI workgroup meetings, National Nodes gatherings, and networking sessions. A HADES hack-a-thon is also confirmed for those looking to dive deeper into tool development.

Social activity: Explore Hasselt via a guided walk in the city on Saturday, July 5th at 17:15 (please indicate your presence in the registration form).
If you want to see a glimpse of the beauty of our city, take a look at this video. 

Agenda Saturday July 5, 2025

The following agenda will be discussed at the WG Surgery and Perioperative meeting (Saturday 5 July, 10-12:30 CEST):

• Workgroup OKRs
• Study progress: Epidemiology of AKI and other complications after major non-cardiac surgery
• Vocabularies related to the 'Procedure' domain. How to use them correctly. Issues and potential solutions

Agenda Sunday July 6, 2025

The Vocabulary WG meeting (Sunday 6 July, 13:30-15:00 CEST) is open to all members of the OHDSI Community and will be of special interest to those converting their data to OMOP CDM and researchers. We will have presentations on two topics:

• Community contribution: the pipeline to incorporate your content in the OHDSI Vocabularies (addition of new vocabularies, concepts, mappings) as well as changes to the content proposed by the community (such as changes to mappings). We will go over the process, timelines, quality assurance and recent examples of the contributions;
• Tracking phenotype (cohort definition) changes dues to Vocabularies changes. Over releases, Vocabularies content changes, which may lead to changes in existing cohort definitions. We will showcase the open-source tools that enable assessment of the changes due to Vocabularies changes and shifts and current practices to resolve inconsistencies.

Community will have an opportunity to engage in the conversations around these topics as well as ask questions and seek help.

We accept submissions for posters and software demonstrations that will be presented during collaborator showcases. There will be a lightning talk session in which authors of selected abstracts will be invited to briefly present their work.

Submission Guidelines 

We invite you to submit an abstract for presentation at the symposium. Abstracts must demonstrate how the work is connected to OHDSI and relevant to OHDSI’s mission in Europe. 

We particularly encourage submissions that highlight the use of OMOP CDM data networks in generating impactful insights, as well as initiatives that demonstrate the relevance of the OMOP CDM and/or OHDSI tools in advancing the objectives of the European Health Data Space (EHDS). 

All submissions will be reviewed by the symposium organizing committee. Successful posters and software demonstrations will be presented during an afternoon collaborator showcase. 

This year we will again have a rapid fire session where a selected set of abstracts will be presented in 5-min slots during the symposium.

Topics of interest include (but are not limited to): 

• Observational Data Management with a European focus: including interoperability standards, common data model and standardized vocabularies development and evaluation, extract-transform-load (ETL) research and applications, and data quality assessment. 
• Analytics technology and infrastructure: design and implementation of hardware and open-source software solutions that leverage the OHDSI community standards or tools to enable evidence generation. 
• Methodological research: research and development of new analytical methods for evidence generation, and empirical evaluation of method performance. 

Submissions are not limited to finished research but could also focus on future plans to adopt the OMOP-CDM in Europe, share experience in mapping European data, use of networks to generate insights, research directions that may be valuable for the community to initiate collaboration, amongst other related topics.

Requirements

• Please use the template for your submission
• Clearly state the names, affiliations, and emails of all co-authors
• Maximum 1.000 words
• Have the following components: Title, Background, Methods, Results, Discussion/Conclusions, References
• Unpublished in the peer-review literature at the time of abstract submission
• Figures, tables, and equations can be added to the abstract to support description of the methods or results
• Save document as a PDF using the following naming convention: lastname_short-title_2025symposium, where the "lastname" corresponds to the name of the presenting author, and "short-title" should include keywords that summarize the title

How to submit

• Please use the following form for your submission: link.
• If you have any further questions about submissions or the OHDSI symposium please send an email to:  ohdsi.europe2025@uhasselt.be.

Important dates 

• March 31st, 2025: Deadline for abstract submissions 
• May 5th, 2025: Notification of acceptance and selection for lightning talk sessions
• June 16th, 2025: Registration deadline
• July 7th, 2025: European OHDSI Symposium in Hasselt

If you have any further questions about the 2025 OHDSI Europe symposium, please send an email to: OHDSI.Europe2025@uhasselt.be.