The global digital health market size is projected to grow from $332.53 billion in 2022 to over $900 billion in 2032. Digital health technologies make a significant impact on the level of patient engagement and satisfaction with the healthcare services they receive. Recently, we discussed the evolution of healthcare data standards in the U.S. and described the initiatives that provide patients with advanced control over their healthcare data. But today, we will discuss how to implement FHIR for startups and how to create an FHIR implementation guide.
Patients now make good use of the freedom granted to them by government bodies to achieve more patient-centered care. For example, citizens of the United States can choose any app they like to connect to an EHR and display personal health data. We discussed a patient’s authorization use case in our article about SMART on FHIR. SMART on FHIR reduces costs and time for new app implementation. FHIR implementations allow for the development of patient-facing health applications with FHIR that can integrate with different healthcare systems and provide patients with personalized health information and insights.
Also, in our article about regulatory compliance in healthcare, we talked about the Dutch experience and how the MedMij standard promotes the digital exchange of health data between patients and healthcare professionals. Public institutions worldwide realize the importance of EHR interoperability and dedicate their efforts towards achieving it.
The HL7 FHIR standard has become a leading solution in different countries for facilitating interoperability in healthcare. The standard became more popular thanks to the standardized approach to healthcare data exchange. Also, to ensure that FHIR is not a burden for healthcare stakeholders. To ensure proper adoption, HL7 offers a tool known as the SMART on FHIR implementation guide, which supports scalable interoperability and simplifies system-wide integration.
Intended audience
Every FHIR implementation guide is written for someone specific. Some are aimed at EHR vendors and app developers. Others target payers, labs, public health teams, or national programs. This matters because the IG usually assumes certain workflows and data realities. If the audience does not match your ecosystem, you end up fighting the guide instead of using it.
Scope and usage
Scope is the “what” and “why.” It defines the use cases the IG supports and what is out of scope. Usage is the “how.” It explains which resources to use, which profiles and extensions apply, what “must support” means, and how exchange should work in real workflows. Teams that treat an IG like a checklist of profiles often miss the actual intent behind the rules.
Boundaries and relationships
IGs rarely stand alone. Most depend on other standards, terminologies, and baseline profiles. They may bind codes to SNOMED CT, LOINC, ICD-10, or RxNorm. They may align with certification programs or national policies. Some IGs build on other IGs. Understanding these relationships helps you reuse the right pieces and avoid conflicting constraints.
Read Also: FHIR vs. HL7: What to Choose
FHIR IMPLEMENTATION GUIDE (IG) AND ITS CONTENTS
What is an FHIR Implementation Guide?
An implementation guide FHIR is a set of detailed instructions for implementing the FHIR standard in a specific healthcare context. It complements a proper FHIR server implementation by defining how resources, profiles, and operations should behave in a real-world environment.
Why do we need profiles?
FHIR is an international specification that covers many different contexts in healthcare (e.g., patient management, medical billing, scheduling, etc.). It is one of the most flexible healthcare data standards since FHIR Resources standardizes about 80% of use cases in healthcare. Profiling allows for coverage of the 20% of use cases that fall outside the core FHIR specifications.
A profile is a StructureDefinition FHIR resource tailored to a specific use case. It is one of the main FHIR artifacts. A profile defines rules, extensions, and constraints for a resource. Therefore, profiling is the essential step in the FHIR standard implementation — especially when you’re planning to build FHIR infrastructure from scratch or adapting existing systems.
Read Also: How Australian Digital Health Is Embracing FHIR Standards
FHIR ARTIFACTS
FHIR profile: contents of an FHIR profile vary due to differences in requirements and regulations of different healthcare ecosystems. However, all profiles include components that define constraints and extensions, the structure of a resource, and rules for its usage. To gain a deeper understanding of the FHIR standard and its significance in healthcare interoperability, it’s essential to explore what is FHIR.
FHIR terminology: one of the key FHIR components that ensures the consistency and accuracy of exchanged data. FHIR terminology consists of:
| CodeSystem | a set of codes that represent the medical concepts in FHIR resources |
| Value Sets | a set of codes from one or more CodeSystems intended for a particular context |
Hl7 FHIR tutorial Implementation Guides may include terminologies required to make the IG work.
Terminology allows for the correct interpretation of healthcare data regardless of the systems participating in the healthcare data exchange. In addition, FHIR security ensures that sensitive healthcare information remains protected during data exchanges.FHIR terminology impacts clinical decision-making by defining codes representing clinical concepts in FHIR resources that allow for meaningful use of healthcare information.
Search Parameters: in the context of FHIR, search parameters are used for retrieving FHIR resources that satisfy a set of conditions. Search parameters define the criteria for searching specific healthcare information within FHIR resources. Earlier, we answered common questions about FHIR Search, so you should check this article out to learn more about FHIR search parameters.
The IG may determine search parameters to make an FHIR Implementation Guide work with a specific FHIR or custom profile.
FHIR Operations:
FHIR Operations refer to operations that can be performed on FHIR resources. The operations in FHIR are based on RESTful principles and use HTTP protocol. FHIR operations include the following components:
1. The base URL (the URL of an FHIR server used for accessing a resource);
2. Resource Type (e.g., “Patient”, “Encounter”);
3. Operation Type (e.g., create, read, update, delete);
4. Parameters (allows for additional search parameters that do not affect the server’s state).
FHIR Implementation Guides may include a requirement for the utilization of standard FHIR operations designed for specific use cases. In an HL7 FHIR implementation guide, operations are often constrained or extended to support national or organizational interoperability scenarios. A Guide can define operations to cover the use case that underlies that particular implementation guide.
Conformance and Validation
Conformance is what you claim you support. Validation is how you check it. Most integration pain comes from gaps between the two.
Conformance statement
A conformance statement describes your system’s behavior in plain terms. Which profiles do you support. Which operations and searches work. What is required versus optional. What are the limits. This helps partners integrate without “trial and error” calls and guesswork.
Validation tools
Validation tools check resources against the IG rules. They cover structure and data types, profile constraints, terminology bindings, and sometimes reference rules. Many teams also add workflow checks, because not everything important is purely structural. The most practical setup is validation in CI for test data plus validation at ingestion, so issues are caught early and with clear error messages.
HOW TO FIND A FHIR IMPLEMENTATION GUIDE
Sometimes it’s easier to create a new FHIR implementation guide for a specific use case than to find an existing one that fits. Despite the large number of IGs available, the FHIR specification doesn’t clearly define where to locate or store them. Still, there are several resources you can explore before starting to develop your own guide.
FHIR Implementation Guide Registry
As the name implies, the site features a collection of Implementation Guides that developers of new health IT solutions and other stakeholders can use to find an IG to set their project on FHIR.
The FHIR IG Registry includes only the Creating & Publishing FHIR Packages the FHIR community balloted for. That is a main peculiarity of the FHIR standard since it was the first standard for the healthcare industry designed by developers, not clinicians. The website includes the existing IGs available for browsing by filters (e.g., by country, release, product, contents, category, etc.).
The FHIR IG registry is the first website to check when considering leveraging the FHIR standard and see the IGs from the National Base category to discover FHIR implementation journeys for countries such as the U.S.
Need an FHIR IG example?
The US Core FHIR Implementation Guide provides a set of requirements for adopting the profiles included in the US Core. The Office of the National Coordinator for Health Information Technology (ONC) sponsored the development of the US Core Requirements.
The US Core benefited mainly from the testing and guidance of The Argonaut Project‘s team (one of the primary FHIR accelerators in the U.S.). The US Core Implementation Guide includes the following:
- Introduction and background information;
- The conformance rules and general requirements for all actors;
- The mandatory elements to support;
- Guidance for the use of profiles and transcriptions for profiles from the guide;
- Data classes and data elements for US Core profiles;
- Guidance on medication access for patients and providers;
- FHIR Artifacts: detailed description for all FHIR objects for this guide;
- A set of profiles and extensions defined in the guide for data exchange;
- Search parameters and operations used for US core transactions;
- Terminology: value sets and code systems for US Core profiles;
- The expected FHIR capabilities for actors;
- General security requirements and recommendations (the complete list is available at http://hl7.org/fhir/us/core/).
The Implementation Guide provides constraints on FHIR resources and the set of FHIR RESTful interactions required to create US Core Profiles and access patient data. The main goal of the US Core IG is to promote interoperability and the adoption of the FHIR standard to improve healthcare data exchange in the country.
Read Also: Mapping Healthcare Data to HL7 FHIR Resources
Authoring and Distributing IG
Implementation guides are not just PDFs. They are versioned specifications that teams need to publish, consume, and maintain. Authoring is about defining profiles, extensions, value sets, and examples in a way that tools can process. Distribution is about making sure implementers can reliably find and use the right version.
Authoring implementation guides
Authoring usually means creating profiles and rules that turn base FHIR into “your” FHIR. That includes defining required fields, terminology bindings, cardinality rules, and constraints on references. It also includes writing narrative guidance and providing real examples, because examples are what developers actually follow. Most teams also define test scenarios and error expectations early, so validation is not a surprise later.
Distributing implementation guides
Distribution is how the IG becomes usable across teams and vendors. In practice, implementers consume IGs through published packages and registries. Common channels include the HL7 package ecosystem, the IG Registry, and platforms like Simplifier. The goal is simple. A developer should be able to pull the IG, validate against it, and know exactly which version they are implementing.
HOW TO CREATE A FHIR IMPLEMENTATION GUIDE
Creation Tools
Here are some FHIR implementation Guide creation tools in the market:
The FHIR Implementation Guide (IG) Publisher
The first tool mentioned on the IG Registry website is the IG Publisher. It is a creation and publishing FHIR Packages platform, which allows for converting materials into XML, JSON, and TTL formats. Building the IG with the IG publisher involves four steps:
- The IG publisher installation;
- Defining the resources that will form the foundation of the Implementation Guide;
- Developing the structure and content of the Implementation Guide;
- Running the IG publishing process.
The IG Publisher is a powerful tool that supports various programming languages, bundles, and spreadsheets. Thus, the diverse options guarantee the accessibility of the IG Publisher’s functionality to all stakeholders requiring a comprehensive FHIR Implementation Guide creation tool.
Simplifier.net
This platform encourages the reuse of existing profiles and extensions by providing a centralized repository and support for various searching options (e.g., IGs developed for international or regional projects). In addition, the site offers free and paid plan options for developers.
In one of our previous articles, we discussed the FHIR profiling tools. The list of the best FHIR profiling tools includes:
- The Kodjin Profiler Tool
- The Forge from Fire.ly
- Trifolia-on-FHIR
Why do we need profiling tools?
The process of an FHIR Implementation Guide involves identifying the specific resources, profiles, extensions, and terminologies that provide the basis for it. The FHIR profiler allows for automatizing the profiling process so that a developer can customize an FHIR resource faster and easier.
Apart from that, a profiling tool improves the accuracy of a profile since it ensures that it complies with the FHIR standard. A profiling tool helps to create consistent profiles and extensions in no time. Check out our article about FHIR profiling tools to discover how to choose and use them.
Multi-Version Implementation Guides
Supporting multiple IG versions is common, especially when partners upgrade at different speeds. Teams usually handle this by treating the IG version as part of the contract. You keep versioned packages, versioned profiles, and clear routing logic. For example, one partner sends data under one version, another partner under a newer version. You validate each stream against the right rules, and you map forward into a stable internal representation. This approach avoids forcing a “big bang” upgrade and keeps integrations stable while the ecosystem catches up.
HOW TO IMPLEMENT FHIR
However, FHIR implementation can be quite complex since it requires deep knowledge of the ever-changing domain requirements. Kodjin’s certified FHIR and profiling experts are ready to help you with an FHIR Implementation Guide development.
The Kodjin Interoperability Suite includes advanced FHIR-based tools with proven performance under national-level projects. Our team will help you define the scopes for Guide, complete the profiling, and ensure the IG’s conformance to the FHIR standard.
We use our extensive experience to help clients leverage FHIR standards for better healthcare and streamline operations. Contact us to learn more details about our enterprise-level solutions.
Understanding and applying FHIR data standards is critical for consistent data modeling, interoperability, and ensuring that all healthcare systems interpret patient information accurately.
Real-world Examples of FHIR Implementation
FHIR for a National eHealth System
The Ukrainian healthcare system needed a significant change because healthcare professionals still used paper documents. The Edenlab team built a new and modern health system for the whole country using the FHIR standard. It resulted in a healthcare system with over 36,5M patient records that can be easily shared with doctors and patients. This project stands as a prime example of applying FHIR rule solutions and FHIR guidelines at a national level — one of the largest FHIR-driven systems worldwide.
HEALTH.ASIA: FHIR for Accurate Auto-adjudication of Medical Claims
For Heals.Asia, a major company in Hong Kong that processes insurance claims, Edenlab’s team created an auto-adjudication engine using FHIR. This FHIR HL7 rule engine is capable of handling complex limits and rules for insurance plans, such as deductibles, co-pays, co-insurance, out-of-pocket maximums, family limits, and min/max patient age. The team conducted mapping to the currently existing documents and created FHIR profiles. As a result, the client received a fully functional FHIR-based auto-adjudication engine that efficiently handles these different rules and constraints.
Conclusion
Healthcare data interoperability has become a task of national scale and importance in many countries, so FHIR is on everyone’s minds today. FHIR can significantly simplify health cloud implementation by providing a robust base for interoperable exchange, resulting in improved consistency and quality of exchanged data.
FAQ
Are there any specific tools or resources that can aid in FHIR adoption?
The Kodjin Interoperability suite includes all the needed tools for effective adoption of the FHIR standards, such as:
- Kodjin FHIR Server: the powerful tool for managing, validating, and storing healthcare data.
- Kodjin Terminology Service: allows for working with standard and proprietary terminology systems.
- Kodjin FHIR Profiler: automates and speeds up the creation of dynamic FHIR profiles.
- Kodjin FHIR Mapper: allows for mapping healthcare data to HL7 FHIR resources for improved interoperability.
How can healthcare providers ensure compliance with FHIR standards and regulations?
The strategy for achieving regulatory compliance in healthcare depends on the location of a stakeholder. The European regulations are different from the US ones and we highly recommend you reading our article about regulatory compliance in healthcare where we discussed this topic in detail.
Can FHIR be integrated with existing healthcare systems, such as EHRs and HIS?
Integration of the FHIR with existing healthcare systems is possible with proper tools, the knowledge of the healthcare domain, and an exceptional expertise in FHIR.
What is the 80/20 rule in FHIR?
FHIR is designed to cover the common cases out of the box. That is the “80.” The remaining “20” is the local, domain-specific, or country-specific detail, and that is what profiles, extensions, and implementation guides are for. The takeaway is simple. Use standard FHIR where it fits, and use controlled customization where it does not.
How to implement a FHIR server?
Start with the basics: choose a FHIR version, choose the IGs you need to support, and define your role. Are you a data store, an API layer, a gateway, or all three. Then build core capabilities like create, read, update, search, paging, and security with OAuth2 and scopes. Next, add validation against your IGs and publish your conformance statement so partners know what to expect. After that, you can layer in features like subscriptions, bulk export, terminology services, and audit logging, based on your use cases. Finally, test with real partner payloads. That is where most gaps show up.
