Product Manager at Relevant Software

HL7 Standards: The Evolutionary Leap in Healthcare Data Exchange

August 25, 2023

In healthcare, providers and payers employ a great variety of software tools and tech solutions. But before HL7 standards came into the picture, facilitating communication between different healthcare systems was quite an ordeal. 

While each device brought unique benefits to specialized medical processes, these tools often operated independently, leading to an incoherent data flow. Every interface demanded its own bespoke set of standards for data sharing. The push toward digital medical records added fuel to this fire, emphasizing the urgent need for seamless integration, especially as Electronic Medical Records (EMRs) started working alongside other systems for billing and appointments. 

But the introduction of HL7 standards changed the game completely. Interested in understanding their pivotal role? Our article sheds light on it.

What are HL7 Standards?

When we mention HL7 or Health Level Seven, we are talking about the Standards Developing Organization accredited by the American National Standards Institute. It formulates consensus-based standards, reflecting diverse perspectives from healthcare system participants.

HL7 standards

So, when you ponder what HL7 standards are, think of them as a series of message formats and associated clinical standards that define the best way to present clinical data. But why the number “7”? It breaks the vast world of HL7 into manageable components, each serving its own unique purpose.

  • Primary Standards: At its core, these standards set the key benchmarks, playing a vital role in guiding system interactions while emphasizing compliance.
  • Foundational Standards: These standards act as the groundwork, spelling out the critical protocols and tech underpinnings that every organization should adopt.
  • Clinical & Administrative Domains: Specifically crafted for the healthcare community, these shed light on documentation norms and simplify the merger of structured documents with routine messaging tools.
  • Medical Systems Profiles: Delving into the specifics, this segment breaks down how Electronic Health Records (EHR) are managed and profiled.
  • Implementation Guides: These are packed with instructions on best practices to ensure smooth and effective solution rollouts.
  • References: They clarify the regulations and tech essentials crucial for anyone diving into health software creation.
  • Education and Awareness: This set keeps users informed about the latest in HL7 and arms them with what they need for a seamless transition.

The HL7 standard is often referred to as a “non-standard standard.” Though it might sound paradoxical, it underscores the uniqueness of every hospital, clinic, imaging center, lab, and care facility. Given their distinctiveness, one can’t really pin down a one-size-fits-all business or clinical model for patient interactions, handling clinical data, or dealing with associated staff.

The Origin and Evolution of HL7 Standards

From its inception in the 1980s, HL7 has been on a relentless journey, adapting and refining with the times. Starting as a basic framework for data exchange, it matured over time, responding to the ever-growing healthcare sector demands. Every iteration, from the rudimentary HL7v1 to the intricate functionalities of HL7v3 and FHIR, has been about moving closer to the seamless, efficient, and secure healthcare data exchange.

Evolution of HL7 Standards

Types of HL7 Standards

With several versions and types, understanding HL7 standards is pivotal to grasping the present and future of healthcare integration. So, for a start, read about the varying types of HL7 standards and their role in our ever-evolving healthcare landscape.

HL7 Version 2.x

Debuted in 1989, this was the version that paved the way for many of the healthcare interoperability standards we see today. It’s event-driven and primarily focuses on interfaces between systems. One of its major appeals? Flexibility! Systems can choose which messages they want to support, which segments they’ll use, and even add custom segments. In essence, it’s the free spirit of the HL7 family.

Now, while flexibility is its forte, it’s also its Achilles’ heel. This means that no two 2.x implementations are ever truly identical. And let’s be frank: it’s aging. It’s not as equipped to handle the latest tech innovations in healthcare. Plus, with no standard method for extensions, customization can lead to compatibility issues.

HL7 Version 3

Designed with a fresh approach, it employed a Reference Information Model (RIM) for more structured data definitions. And let’s not forget about its XML-based messaging. It tried to address the wild west customization issue of v2.x by being more prescriptive. 

But ah, the best-laid plans. Version 3 is complex – very complex. Implementing it requires a steep learning curve. And while it aimed for universal compatibility, the rigid structure made it a bit unwieldy for real-world scenarios.

HL7 Clinical Document Architecture (CDA)

A member of the HL7 v3 family, CDA stands out by standardizing the structure of clinical documents. These could range from discharge summaries to imaging reports. It utilizes XML, making documents both machine-readable and human-readable. The elegance of CDA lies in its structured format while allowing for narrative content.

The gripe with CDA? While it standardizes structure, it doesn’t standardize the actual content, leading to potential inconsistencies. Moreover, its heavyweight XML structure can sometimes be overkill for simpler applications.

HL7 Fast Healthcare Interoperability Resources (FHIR)

Last but by no means least, HL7 FHIR (pronounced “fire” – and it’s indeed on fire in the interoperability healthcare tech scene). FHIR combines the best features of HL7’s v2, v3, and CDA while also leveraging the latest web standards. It’s a model for electronic exchange, with resources being its main building block. It’s fresh, it’s web-based, and its modular components can be used in various settings, from mobile phone apps to cloud communications.

But before we crown it king, FHIR is still evolving. Being the newest, it’s not as widely adopted as its predecessors. There are concerns about data integrity when using FHIR for data storage, and managing the transition to FHIR from older systems can be daunting. Yet, with the trusted vendor, HL7 FHIR Implementation becomes much easier.

The Core Components of HL7 Standards

Now, let’s delve into the core components of HL7 Standards:

Components of HL7 Standards

1. Message Structure and Types

At its heart, HL7 standards define a hierarchical structure for messages. Each message type serves a distinct purpose, such as patient registration, lab results transmission, or billing information. This component ensures that every piece of data transmitted adheres to a consistent and recognized format, facilitating straightforward interpretation by receiving systems.

2. Segments, Fields, and Components

Messages in HL7 are divided into segments, similar to sentences in a paragraph. Each segment contains fields (akin to words in a sentence analogy) that convey specific data. Further granularity is achieved through components within these fields. This meticulous breakdown ensures that each tiny bit of information has its rightful place in the message.

3. Z-segments

Flexibility is key in the dynamic world of healthcare. Z-segments offer this by allowing users to include custom data segments that might not be part of the standard HL7 definition. They ensure that organizations aren’t handcuffed by the standard but can instead tailor messages to their unique needs.

4. Trigger Events

These are the catalysts of the HL7 world. A trigger event is an occurrence, like a patient’s admission, that prompts the sending of an HL7 message. By standardizing these events, HL7 ensures that systems communicate promptly in response to significant healthcare activities.

5. Message Control ID

In the bustling corridors of digital healthcare communication, confusion can easily reign. The Message Control ID acts as a unique identifier for each HL7 message, ensuring messages are processed correctly and not duplicated or overlooked.

6. Acknowledgment (ACK) Messages

Communication is a two-way street. When one system sends an HL7 message, the receiving system responds with an ACK message. This acknowledgment confirms the receipt of the original message and can indicate its successful processing or highlight any issues encountered.

7. Versioning

With advancements in healthcare and technology, the HL7 standard itself evolves. Versioning helps keep track of these changes. By specifying the HL7 version being used, systems can ensure compatibility, ensuring that they “speak the same language”.

The Role of HL7 Standards in Healthcare

Dive into any corner of modern healthcare, and you’re bound to encounter the impact of HL7 standards. For those scratching their heads wondering, “What are HL7 standards and their role?”, let’s make this crystal clear:

Electronic Health Records (EHR) 

EHRs have revolutionized how healthcare operates. Gone are the days of sifting through endless paper trails. Now, everything’s digital and just a click away. But here’s the catch: what good is an EHR if it doesn’t “speak” the same language as other systems?

All is clear as day. HL7 healthcare standards act as translators, ensuring that EHR systems across different facilities and even countries can seamlessly exchange data complying with HIPAA regulations. Think about it: a patient in Boston visiting a specialist in New York? No problem. Thanks to HL7 standards, their entire medical history can be readily accessed, ensuring continuity of care. The HL7 API standards further streamline this, making integrations smoother and more efficient.

Laboratory Information Systems (LIS)

When you give a blood sample, do you ever wonder how your doctor gets the results so quickly? That’s HL7 at play once again. Laboratory Information Systems (LIS) are crucial in diagnostics, and with HL7 standards, they can swiftly send results to clinicians.

But there’s more. Different labs have different systems, and healthcare data standards HL7 ensures they all are in sync. This means that no matter where the test is done, the data can be reliably sent, received, and interpreted. Accuracy and speed? That’s the name of the game in diagnostics, and HL7 makes it possible.


Radiology has its own unique challenges. Imagуfiles are massive, and they come with a plethora of associated data. Now, let’s say a patient gets an X-ray in one facility and an MRI in another. Both facilities need to communicate and share this data flawlessly for accurate diagnosis and treatment.

HL7 standards in healthcare come to the rescue. Radiology departments use these standards to ensure that image files, along with their annotations and diagnostic reports, are easily transferable and accessible by different healthcare providers. The interoperability facilitated by HL7 ensures that a radiologist’s insights are never lost in translation, regardless of the technology used.

HL7 Standards in Radiology

Current Trends Influencing HL7 Standards

The healthcare landscape is constantly evolving, and with it, the technologies that underpin it. HL7 standards, or as the insiders like to call it, “health level seven,” have long been the cornerstone of healthcare interoperability. But like every other sector, healthcare doesn’t exist in a vacuum either. Trends are emerging, technologies are advancing, and standards like HL7 must keep pace. Let’s dissect some of the game-changers influencing these standards.

The Shift Towards FHIR

Talk to any healthcare tech enthusiast, and you’ll hear them rave about FHIR (Fast Healthcare Interoperability Resources). But why all the fuss? Well, FHIR is essentially the newest kid on the block in the world of HL7 and FHIR standards. It’s the shiny new tool promising to revamp healthcare interoperability.

FHIR focuses on simplicity. Instead of navigating the complex web of healthcare data structures, FHIR implementation introduces a more intuitive way to represent clinical documents. It offers a more flexible approach, breaking down information into smaller data chunks called “resources.” These resources can represent anything from a patient’s details to their medications, making it easier for EMR HL7 standards to work in harmony.

But it’s not just about breaking down clinical documents into bite-sized pieces. FHIR’s true strength lies in its ability to integrate seamlessly with modern web technologies. This ensures that health level seven standards evolve with the times, fostering better and more efficient healthcare workflows.

Impact of Cloud Computing on HL7 Standards

Remember when storing patient data meant rooms filled with filing cabinets? Those days are long gone, thanks to cloud computing. But how does the cloud influence HL7 data standards?

Cloud platforms provide scalability and flexibility that traditional systems simply can’t match. As healthcare institutions produce vast amounts of data daily, the cloud offers a solution to store, manage, and analyze this data efficiently. Now, integrating HL7 with cloud platforms means healthcare providers can access clinical documents in real-time from anywhere.

Moreover, with cloud computing, the dream of achieving full interoperability in healthcare is closer than ever. Imagine a world where a doctor in Texas can instantly access a patient’s health records from a clinic in California. That’s the promise of combining the prowess of HL7 standards with cloud computing.

APIs for Healthcare Data Exchange

The HL7 landscape is witnessing a significant shift toward utilizing APIs (Application Programming Interfaces) for fluid data transfers between healthcare apps. Thanks to APIs, these systems now converse more effortlessly, sidestepping convoluted message parsing. The innate support of FHIR for RESTful APIs means that healthcare entities can swiftly roll out interoperable solutions, fully harnessing today’s web tech.

This trend has sparked an upsurge in FHIR-centric APIs and apps, underlining FHIR’s transformative role in healthcare data interactions and paving the way for innovation. As FHIR adoption scales, more applications are poised to debut. Key players include:

  • Apple Health Records: Employs FHIR, enabling iPhone enthusiasts to securely tap into their health records from varied providers.
  • SMART on FHIR: A pioneering initiative that aids developers in creating healthcare apps that mesh seamlessly with current EHR systems, optimizing clinical insights and operational flow.
  • Sync for Science (S4S): A joint venture by NIH and ONC, simplifying the path for individuals to channel their health data into scientific research without a hitch.
  • Epic’s App Orchard: A hub for third-party apps that merge with Epic’s EHR setups via FHIR-focused APIs.

To wrap it up, the world of HL7 is buzzing. With shifts towards FHIR and the increasing dominance of cloud computing and API, the future looks bright for healthcare interoperability. While challenges will always exist, the continued evolution of health level seven promises a more streamlined, efficient, and patient-centered tomorrow. And really, isn’t that the ultimate goal?

Progressive HL7 standards, cutting-edge tech, and an amplified call for interoperability steer the trajectory of healthcare data exchange. As the healthcare arena swiftly transforms, grasping emerging innovations becomes paramount. Seizing these novel opportunities paves the way for refined data communication, seamless processes, and enriched patient experiences.

Teaming up with experienced HL7 specialists like Relevant can simplify the complexities of healthcare software development. Rooted in profound sector insights and versed in modern HL7 norms, our healthcare IT consulting services are primed to guide you in system evaluations, process enhancement, and cultivating resilient data communication strategies.

Contact us to stay adaptable in a continually metamorphosing healthcare domain.


Tags: healthcare

Written by
Product Manager at Relevant Software
For more than 6 years, I've been working as Business Analyst and Product Manager at Relevant. I'm responsible for requirements engineering and management and solution implementation control.

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