Health Level 7 (HL7) International is an ANSI-accredited, standards-developing organization founded in 1987 with members in more than 50 countries. HL7 International was created with the goal of developing a framework and standards that support the exchange and sharing of electronic health information among applications. Without a standard, consistent framework for exchanging data, exchanging data between healthcare systems required the development of custom interfacing systems, which are costly and time-consuming to develop. Jump to resource links -->

What are the HL7 Standards?

The HL7 standards are a set of messaging standards that aim to create a consistent messaging framework to allow clinical applications to seamlessly exchange data. More than 90% of healthcare facilities and the largest health information system vendors today use the HL7 standards. HL7 is used by clinical interface specialists, healthcare application vendors, government entities, and medical informaticists. There are several versions of the HL7 standards, including:

  • HL7 Version 2, which is the most widely used HL7 protocol meant to facilitate clinical communications.
  • The more-powerful HL7 Version 3, which offers additional capabilities for medical informaticists and also supports government reporting requirements.
  • EHR-PHR System Functional Models, which provide common language parameters for developing EHRs and their underlying components and standards for PHR functions to support data exchange between EHRs and PHRs.
  • Clinical Document Architecture (CDA), which establishes an exchange model for clinical documents.
  • Fast Healthcare Interoperability Resources (FHIR), a draft standard built around HL7 versions 2 and 3 that uses web-based API technology to streamline the development of interoperable healthcare applications.

The HL7 standards are grouped into four primary reference categories:

  • Section 1: Primary Standards – Including the most frequently used standards, HL7’s primary standards are the essential standards for system integration, interoperability, and compliance.
  • Section 2: Clinical and Administrative Domains – This section includes messaging and documentation standards for clinical specialties.
  • Section 3: Implementation Guides – This section includes implementation guides and support documents providing supplemental materials for other standards.
  • Section 4: Rules and References – This section includes technical specifications, guidelines, and programming structures for software development and standards development.

Benefits of the HL7 Protocol

The HL7 protocol defines how data is packaged and exchanged by setting the language type, data structure, and types of data to support seamless integration between applications and systems. The HL7 protocol aims to allow healthcare organizations and applications using the HL7 messaging standard – even those that speak different languages – to communicate and share data.

A common language and consistent data structure eliminate ambiguity and the risk of misinterpretation, while also eliminating the need to develop custom interfacing systems. As a result, healthcare information systems vendors can eliminate lengthy and costly integration projects, bringing applications to market faster and giving healthcare organizations more choices when adopting new information systems.

Challenges of Implementing the HL7 Protocol

The HL7 protocol was designed to be flexible, allowing extensive customization for easy adoption, and applications can use different HL7 formats or adopt different aspects of the HL7 protocol. As a result, there are unique implementations of the framework from one organization or application to the next, making interfacing between disparate applications difficult. Overcoming these integration challenges requires a significant investment in integration development.

While HL7 Version 2 remains the most widely used, industry-accepted protocol for exchanging clinical data between systems and applications, there’s a continued push for greater interoperability. Continued adoption of HL7 and the emergence of FHIR create opportunities for developers to create new and innovative tools to support the seamless exchange of healthcare data.