Too many profiles, not enough reuse: Insights from 1,300 FHIR packages

Dijs completed a research internship with Firely, where he focused on an in-depth analysis of FHIR, exploring adoption metrics and comparative modeling approaches to uncover insights on global interoperability. Below is a snapshot of what he discovered.

Updated April 23, 2026

Have you ever wondered how a global health data standard actually works in practice?

Last year, driven by curiosity and the support of Firely, I undertook an analysis of over 1,300 FHIR packages from Simplifier.net, a global hub for health IT collaboration. I wanted to understand how FHIR is really being used in the real world, and what that tells us about global healthcare interoperability.

Simplifier.net: A global collaboration hub 

Simplifier.net is a key online library for FHIR projects around the world, hosting packages of related profiles. These packages typically include customized profiles, which are specialized extensions to standard resources like Patient, Observation, Medication, and Encounter.

By analyzing metadata provided by Simplifier.net, such as downloads, views, declared dependencies, and version histories, I was able to achieve a unique, data-driven perspective on global FHIR adoption trends, patterns of profile reuse, and collaborative behavior among implementers. 

The dataset analyzed consisted of 1,319 distinct FHIR packages from 602 projects spanning 53 jurisdictions, which provided a rich foundation to investigate several critical questions: Which countries are leading in FHIR adoption? Are communities effectively reusing existing profiles, or are they repeatedly reinventing the wheel? 

Five countries leading the way 

Among the 57 countries analyzed, five stood out clearly due to their significant activity and contributions: Germany, the United States, Canada, the Netherlands, and the United Kingdom. 

Germany: Setting the standard for reuse 

Germany emerged as a clear leader, producing a high number of packages and becoming a global benchmark for profile reuse. German-origin packages accounted for approximately 39% of global downloads and nearly 47% of worldwide dependencies.

Germany’s success comes from strong national coordination, clear rules, and initiatives like Basisprofile DE and the Medical Informatics Initiative. This setup builds trust, makes it easier to reuse profiles, and helps healthcare systems collaborate more smoothly, both locally and globally.

United States: Active but highly fragmented 

The United States shows substantial FHIR activity, evidenced by a large number of implementation guides and packages. However, the country’s decentralized and market-driven healthcare system may contribute to a degree of fragmentation in how FHIR is implemented across organizations.

While national initiatives such as US Core and the Da Vinci Project aim to encourage alignment, available evidence from public registries, tooling practices, and implementation guide structures suggests that many implementers develop custom profiles tailored to local or organizational needs. 

This trend appears to result in multiple profiles with overlapping scopes but limited consistency, which could impact interoperability and reduce the potential for profile reuse. However, it’s important to note that this analysis only includes publicly available FHIR packages; implementations that are private — including those hosted on platforms like Simplifier.net — are not represented.

As such, the full extent of FHIR usage in the U.S. is likely underrepresented in this dataset. Nonetheless, the available data suggests that harmonization across implementations remains a challenge.

Netherlands: Structured flexibility and national coordination 

The Netherlands demonstrated a strong balance between flexibility and structural consistency. At the core of its strategy lies the centrally maintained “NL Core” profiles, which build upon clinician-developed clinical data models known as Zorginformatiebouwstenen (ZIBs).

Although the Netherlands had fewer total projects compared to other leading countries, its profiles achieved high visibility and consistent usage rates. This reflects the high quality, relevance, and structured nature of Dutch profiles, enabled by effective coordination from organizations like Nictiz.

Canada: Diversity in regional implementations 

Canada’s federated healthcare system, characterized by significant provincial autonomy, showed moderate activity levels in package development but exhibited limited reuse and relatively low inter-package dependencies.

Despite the establishment of national “Canadian Baseline” profiles, individual provinces often developed their own distinct profiles tailored to local needs. This regional approach resulted in fragmented efforts, creating barriers to comprehensive national interoperability.

United Kingdom: Centralized Core with regional variations 

The UK presented a hybrid governance model in its FHIR implementation strategy. NHS Digital centrally managed the foundational “UK Core” profiles, offering a consistent baseline for healthcare organizations.

However, regional NHS trusts and vendors frequently developed their own extensions to these profiles independently, leading to limited cross-region reuse.

This regional fragmentation, despite the presence of centralized guidance, significantly impacted the overall consistency and interoperability of FHIR implementations within the country.

Profiliferation: A major interoperability challenge 

A key insight from the study was the widespread occurrence of “profiliferation,” a term describing the rapid proliferation of redundant and overlapping FHIR profiles.

This phenomenon typically arises when teams repeatedly create new profiles for similar purposes instead of reusing or adapting existing ones. Profiliferation makes it harder to share data, raises maintenance costs, and takes away from the benefits FHIR is meant to bring. 

The analysis revealed that environments with strong centralized governance, such as those in Germany and the Netherlands, were significantly more effective at promoting profile reuse, resulting in clear dependency structures and minimized profiliferation.

Conversely, decentralized governance models common in the U.S. and Canada frequently led to isolated development efforts and substantial profile fragmentation, posing considerable challenges to interoperability.

Common challenges in profile quality and consistency 

An in-depth analysis of profile content quality uncovered several recurring challenges that impacted effective reuse and interoperability: 

• Incomplete metadata: Many FHIR packages lacked essential documentation, including clear descriptions, versioning information, and intended use statements, reducing their discoverability and usability.
• Unclear profile hierarchies: Inadequately documented profile inheritance structures made understanding lineage and proper reuse challenging.
• Resource overload: The Observation and Extension resources were disproportionately profiled, exceeding the intended 80/20 balance between core and extension profiles. This excessive customization complicated interoperability.
• Duplication of efforts: Frequently, multiple similar profiles developed independently, unnecessarily fragmenting data exchange capabilities and complicating system integrations. 

Addressing these issues requires better documentation standards, stronger governance practices, and standardized approaches to profile creation.

Insights from the heatmap analysis 

A heatmap visualization of adoption metrics provided vivid insights into country-level differences. Germany consistently led across all measured metrics, indicating superior governance and reuse practices. The U.S., despite high activity levels, showed markedly lower reuse rates, highlighting significant fragmentation.

Notably, Simplifier.net’s dataset only includes publicly shared FHIR packages, which means it does not reflect the numerous private-sector implementations prevalent in countries. This transparency gap underscores the importance of open data sharing to fully understand global FHIR usage and effectively address interoperability challenges. 

Recommendations and future directions 

The findings make it clear: if we want better FHIR interoperability, we need to tackle profiliferation and fix the gaps in governance: 

• Strengthening governance structures: Establishing or enhancing national and regional governance bodies to curate, manage, and maintain standardized core profiles.
• Promoting effective reuse: Enhancing registries and discovery tools for profiles, making it easier for implementers to identify and adopt existing solutions.
• Investing in advanced validation tools: Developing automated validation and quality assurance tools to ensure profile consistency and identify redundancy early in the profile creation process.
• Encouraging transparency and openness: Supporting open publication practices for implementation guides, profiles, and metrics, fostering community feedback loops that drive continuous improvement and interoperability.

Final reflections 

My research journey reinforced the idea that the success of FHIR as a standard hinges on collaborative human efforts, clear governance frameworks, and open data-sharing practices. Acknowledging and actively addressing these critical elements can significantly advance global interoperability. 

In essence, achieving meaningful interoperability requires balancing technology, governance, collaboration, and transparency. Let us embrace openness, foster collaboration, and build the interconnected healthcare future we all envision. 

Editor’s note (April 2026)

Since this research was published, the European Health Data Space (EHDS) has moved from policy proposal to active implementation, with member states now working toward compliance timelines that will directly shape how FHIR profiles are governed across Europe. The EHDS essentially codifies at EU level what this research argues from the data: centralized governance and standardized core profiles are prerequisites for meaningful interoperability. For countries still wrestling with fragmentation, and for the organizations building on top of national infrastructures, the EHDS raises the stakes considerably. The question is no longer just whether to reuse profiles, but whether national implementations will be compatible with a shared European baseline.