HL7 vs. Other Healthcare Data Standards: A Comparison

The healthcare industry is one of the most complicated industries when it comes to data standards and regulations. The data formats change with each hospital or practice, which impacts the interoperability and effective use of information.

There are multiple data standards, creating a fragmented network that makes data sharing and coordination difficult. And if you don’t understand which standard does what, integration becomes difficult and affects how effectively healthcare systems communicate.

However, it’s not just the efficiency; every aspect, from technical ease to the sustainability of digital infrastructure, is impacted. While it is not possible to understand every standard, we will look into some of the widely adopted and customized standards.

This includes HL7, FHIR, DICOM, NCPDP, and more. Another important thing to remember is that selecting the right standards depends on the type of data you are going to share. 

For example, if you are sending patient details in text format, then HL7 is your best bet. However, if you want to exchange images of injury or CT scans, then the DICOM standard will be the right choice. If you know the differences between HL7 and DICOM, then data sharing efficiency will go up a notch.

So, you need to learn the healthcare protocol differences; otherwise, it can derail the whole EHR integration project. Now, this article will be your healthcare standards comparison with HL7 to make sure your understanding of each medical data format standard, along with how HL7 integration services compares to them.

Let’s get started!

Understanding the Healthcare Standards Ecosystem

In healthcare, there is more than one data source, and with it come different data formats. And you can not handle these data formats with a single data format or healthcare protocol. There are different message formats, terminologies, documentation formats, and transaction formats.

That’s why depending on a single format can make it difficult to seamlessly share data. Here’s a simple format of different formats and their purpose, governance body, and general use cases for better understanding.

While every category or format shows different capabilities, they rarely operate in isolation. If you want to have an interoperable system, then you can use them in combination, such as pairing HL7 with LOINC codes for lab results.

In short, healthcare protocol differences do not mean the formats and terminologies or any other standards work separately. This is where HL7 plays a crucial role and brings everything together to give you an integration that is seamless and not isolated.

HL7 vs. FHIR: Evolution Within a Family

FHIR (Fast Healthcare Interoperability Resources) is the latest standard developed by HL7 International. It is not a change but an evolution that builds on lessons learned from HL7 v2 and v3, aiming to modernize healthcare data exchange. Let’s take a look at how it evolved from HL7 v2 to today’s FHIR standard.

The Evolution Path

• The first version of HL7 was developed in the late 1980s as a message-based, pipe-delimited format. Moreover, its flexibility and simplicity made it a favorite and drove high adoption, as nearly 80% of organizations adopted it. However, this flexibility often led to inconsistent implementations.

• The next version was HL7 v3, and it was a try at standardizing data with a document-centric, XML-based approach. It was built on the Reference Information Model (RIM), but this increased complexity led to slowed adoption.

• Lastly, the latest FHIR is a resource-based approach, using RESTful APIs and modern web technologies like JSON and XML. This gives developers more flexibility and fits mobile and cloud environments perfectly. 

Here’s a table that tells the healthcare protocol differences quickly:

FHIR is not a replacement for HL7 v2 in the short term, as it has been widely adopted all over the world. This is why many healthcare organizations run hybrid environments, where FHIR APIs layer along with v2-based workflows, enabling modern integration without rewriting core systems.

In short, these standards coexist where HL7 v2 is best for stable, internal message exchanges, while FHIR excels in patient-facing apps, mobile solutions, and cross-system interoperability.

HL7 vs. DICOM: Clinical Data vs. Imaging Data

HL7 and DICOM are two different standards that operate in two completely different data formats. HL7 manages clinical, administrative, and financial data. Meanwhile, DICOM (Digital Imaging and Communication in Medicine) handles the storage, transmission, and annotation of medical images along with their associated metadata.

With different formats comes a different digital architecture. HL7 specializes in text-based, structured information exchange, using message-based, which is v2, or a document-centric, like v3 and CDA models. It works well for clinical workflows, patient records, and billing data. 

DICOM, on the other hand, uses an image object model and service classes to summarize image pixels, acquisition parameters, and patient identifiers into a single interoperable package.

HL7 vs. DICOM

Just like HL7 and FHIR, DICOM and HL7 also work in harmony. HL7 messages carry patient demographics to a PACS, while DICOM ensures images are properly tagged and retrievable. Here, emerging technologies like DICOMweb and FHIR ImagingStudy are pushing toward a unified exchange model. Rather than competing, HL7 and DICOM together form the backbone of comprehensive patient information management.

HL7 vs. Pharmacy & Claims Standards (NCPDP & X12)

Now that we have seen the standards for sharing data in both text and image formats. NCPDP (National Council for Prescription Drug Programs) helps in exchanging pharmacy or medical data; meanwhile, X12 standards handle the financial side. 

• HL7: Specializes in clinical and administrative data exchange within hospitals, clinics, and other healthcare facilities.
• NCPDP: Focus on pharmacy-based transactions, including e-prescription, refill requests, and medication history.
• X12: Handles the financial part, such as insurance verification, claims submissions, remittance advice, and other financial transactions.

Key Differences in the Standards

• Transaction Types

HL7 covers all the clinical and administrative documentation from patient lab reports to admissions and referrals. NCPDP is involved in managing prescriptions and other pharmacy-related benefit enquiries. X12 supports eligibility verification (270/271), claims submission (837), and payment remittance (835).

• Message Structure

Messaging of HL7 is flexible with the pipe-delimited, JSON, and XML formats supporting the exchange. The NCPDP SCRIPT standard is highly structured for prescription data. X12’s EDI transactions are rigid and HIPAA-mandated.

• Processing Modes

HL7 and NCPDP often support near real-time messaging for care workflows, while X12 transactions may run in batch mode for claims processing.

These three standards are an integral part of the healthcare ecosystem and depend on each other to function effectively. The process starts with HL7 with patient admittance, then moves to NCPDP with prescriptions, and lastly to X12 to complete the payment process.

So, using only one standard will not be sufficient, and healthcare organizations need to effectively combine all three standards to gain benefits.

HL7 & Terminology Standards (SNOMED CT, LOINC, RxNORM)

This is where the consistency of the data is maintained. These message standards define how healthcare data is structured and exchanged, while terminologies define what the data means. HL7 provides the syntax and transport rules, and terminologies such as SNOMED CT, LOINC, and RxNORM ensure semantic consistency across systems. Let’s take a look at how:

• SNOMED CT: This terminology offers a comprehensive, multilingual set of codes for clinical findings, diagnoses, procedures, and body structures.
• LOINC: It standardizes laboratory tests, measurements, and clinical observations, enabling consistent interpretation of diagnostic results.
• RxNORM: Ensuring uniform naming for medications, linking brand names, generics, and clinical drug concepts for precise e-prescribing and pharmacy integration is taken care of by this standard.

When it comes to integrating these terminologies into HL7 messages, you need careful mapping. For instance, a lab result sent via HL7 ORU^R01 should reference the LOINC code for the test, not just a local identifier.

So, the best practice is to centralize a terminology server for code lookups, validation, and version control. Governance structures should oversee code adoption, periodic updates, and HL7 binding definitions to prevent drift between message and vocabulary standards. When message syntax and terminology standards work in harmony, organizations achieve true semantic interoperability, enabling not just data exchange, but shared clinical understanding.

Frequently Asked Questions – Healthcare Data Standards