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The role of interoperability ‒ part two: Semantic interoperability is the highest discipline



Professor Sylvia Thun, MD, is university professor for digital medicine and interoperability at the Berlin Institute of Health (BIH) of the Charité – Universitätsmedizin Berlin. For the qualified doctor and engineer for biomedical technology, interoperability is the key to the further development of healthcare IT. Professor Thun discussed this with Cerner interoperability expert and lead solution leader, Axel Biernat, during German Interoperability Days 2021 (Deutsche Interoperabilitätstage 2021).

Axel Biernat: Sylvia, your background is in medical technology. During your medical training, you worked in radiology / radiation therapy at RWTH Aachen University, where you set up the first IHE connector, among other things. You have been on the board of the HL7 user group in Germany since 2006. This is an exciting career, strictly oriented towards the topic of interoperability. Where does this enthusiasm come from?

Sylvia Thun: In fact, the topic fascinated me early on. I came across the Health Level Seven (HL7) communication standard through a consulting assignment for a tender for interoperable systems. From then on, I knew that this is what I want to spend my professional life doing... {laughs}, because we have been dealing with this topic for a while and we will have to deal with it in the future as well. In addition, it is highly complex and ‒ last, but not least ‒ I thought interoperability was immensely important even back then when it comes to creating added value for all stakeholders in the healthcare system, on the basis of uniform data standards. What is it about interoperability that fascinates you, Axel?

AB: My enthusiasm for HL7 goes back to my studies where we discussed the HL7 standard in Version 2 for information systems in healthcare. Today, HL7 Fast Healthcare Interoperability Resources (FHIR) is a standard for me that represents a big step towards real digital healthcare of tomorrow: easy to implement, developed for mobile and cloud-based applications, and enabling facility and cross-sectoral data communication. I am working with my team at Cerner to make this standard usable for our EHR,®. We are currently focusing on the interoperability solution for and I have to say: HL7 FHIR rocks! This is why I am actively involved in HL7 International and am representing Cerner at IHE Germany and in the German Association of Health IT Vendors (Bundesverband Gesundheits-IT, bvitg). We are obviously both very committed to the board of HL7 Germany, Sylvia. What are you currently working on?


“As providers, we focus on simplifying clinical workflows.”
Axel Biernat


ST: The Berlin Institute of Health at Charité (BIH) has implemented projects with HL7 in almost all areas. On the one hand, we harmonize existing data that come from EHR systems, but also from medical devices ‒ from anesthesia machines for instance. Or we support companies right at the start of their standardization projects by preparing the data for them directly in an HL7 format. In addition, we oversee big projects in the medical informatics initiative, where we create core data sets for various use cases, such as pathology reports. Finally, it is always about simplifying the documentation for physicians. Patient information has to be documented quickly and in a structured manner, and it has to be possible to quickly merge the most important information from longform physician letters.


“We are working on the EHR of the future. This gives our customers and partners interoperable and medical product-compliant access to
Axel Biernat


AB: That’s exactly what we, as providers, are focusing on: simplification of hospital workflows for all users. This only happens if systems in the hospital can communicate with one another at the data level. Semantic interoperability is indispensable for this, it is the highest discipline, so to speak. Obviously, this also concerns the transfer of data across the entire continuum of care. In addition, it makes sense that collected data can be used further, e.g. for clinical research or for studies.

ST: Right. It's not just about digitally documenting and billing, but also making data exchangeable between systems: on the one hand for further use in research, on the other hand to increase patient safety. This specifically concerns communication between an intensive care system and the EHR on the ward, for instance. In order to be able to conduct solid research or use AI applications, a lot of high-quality data is required. This does not work with free text and certainly not with incomplete data. A wise use of the data and data exchange means further development of medical science to benefit the patients as well as the medical staff, whose lives have been made significantly easier. For all these developments, standardization is an essential prerequisite. What is your experience with standardization in Germany, Axel? Where do we stand?

AB: We currently have a standardization model in Germany that is based on shared responsibilities. gematik and KBV (by means of the development of the so-called ‘medical information objects’ (Medizinische Informationsobjekte, MIOs) as well as the Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM) play key roles. Stakeholders from areas such as self-government, specialist societies, science, standardization and industries are included in this model. As an established provider of healthcare IT with global EHR expertise and numerous development partnerships, Cerner is actively promoting the topic of interoperability through standardization. The introduction of the electronic health record, access to digital health applications, concepts like ‘apps by prescription’ and the advancement of telemedicine have recently contributed to a long overdue development boost in Germany. How do you experience standardization in your daily work, Sylvia?

ST: There are many areas, especially when it comes to devices, where there are established, long-term standards today. This makes sense since devices cannot work without standards. In areas where humans do the work, however, there are hardly any IT standards. A coordinating body for Germany is urgently needed here and, according to the legislature, should now also be set up – along with a national coordinator for IT and interoperability, including additional experts. The legal domicile will be at gematik. Speaking of which, gematik is now finally working with international standards. We are very pleased that the legislature has recognized the need for comprehensive standardization. But these developments have not yet been implemented, tested or evaluated. It is not for nothing that we are at the bottom of international rankings in this area in Germany.

AB: Most recently, the German Corona Consensus (GECCO) showed that everyone can make it happen if they really want to. GECCO is a standardized data record that was developed within a short period of time to collect uniform study data for COVID-19 research. You were an integral part of this project. What can you tell us about it?

ST: With the GECCO data record, we showed during the pandemic how quickly we can bring researchers together to create such a record. The same applies to the Corona Component Standards (cocos) initiative of the health innovation hub (hih). All of this shows that if we work together, if we let our expertise flow into the joint project and if the framework conditions are also right, we will make good progress on the matter.

AB: Many hospitals are already promoting their digitization in a structured manner. However, is everyone sufficiently prepared for the topic of interoperability?


“HL7 FHIR is a standard with huge potential.”
Sylvia Thun


ST: Hospitals know the challenges of interoperability well. But if you want more than just pushing ICDs, OPS and personal data back and forth, then you have to delve much deeper into the technical content. This is the next step and this issue can only be solved through interoperability on all levels ‒ on the organizational, structural, syntactic and semantic level. Did you experience this as well, Axel? 

AB: Yes, absolutely. This is right in front of us now, incorporated into law: it is no longer about the provision of documents, but rather about the provision of data for their exchange. Because of that, the KHZG promotes open standards, such as FHIR, as well as ontologies such as SNOMED, which can present medical information semantically correctly. How does this affect your work?

ST: This means that parallel to Version 2 of HL7, we are expanding our experience with FHIR because it is a standard with huge potential. As with all new developments, the first thing to do here is to build up expertise. It requires users who implement new systems, communication servers and terminology servers on site, who manage them and extensively test them in routine operations. This leads to my next question, Axel: many hospitals rely on Cerner, which is used in hospitals of different sizes around the world. How do you implement interoperability?

AB: We are planning a supplementary solution for that will be available in the first quarter of 2022. This solution will also support complementary standards such as 'Smart on FHIR'. In order to facilitate the integration into the IT landscape of a hospital, we will, among other things, implement IHE profiles and relevant FHIR implementation guides, such as ISiK (Informationstechnische Systeme in Krankenhäusern; IT systems in hospitals) in Germany. Semantic interoperability is supported by an integrated terminology server. Our clients will find out more about this in our next blog post on interoperability.

Dear Sylvia, thank you very much for the interview.

ST: Thank you, Axel, for inviting me to this expert talk.