HL7 FHIR

From Clinfowiki
Revision as of 03:16, 1 August 2015 by Kpinsky (Talk | contribs)

Jump to: navigation, search

FHIR – A new standard in interoperability, prime for cloud-based applications

What is FHIR?

FHIR is an interoperability standard created by HL7. FHIR stands for Fast Health Interoperable Resources and utilizes a more modular approach to inter-system messaging than previous HL7 standards versions. These modules are termed “Resources” and allow implementations to be more flexible to changing system processes than traditional V. 2 or 3 standards. The initial version of FHIR was created in 2012 and has undergone multiple revisions to date. There is currently an implementation standard but it is in the draft standard for trial use (DTSU) phase and not yet fully approved. Balloting for the current DSTU is slated for April of 2015 with a projected release of DSTU 2 for July of 2015. [1] Rather than using multi-element structured messages such at HL7 v. 2, 3, and CDA standards, FHIR uses application programming interfaces (API’s) that call for specific elements vs. the entire message as in the other HL7 standards. These APIs utilize a RESTful architecture that is specifically designed for web applications.[1][2] REST stands for Representational State Transfer which allows for exchange of resources on an as needed basis, typically communicated via widely used HTTP or HTTPS protocols.[3]

FHIR Governance

FHIR is actually governed by three separate bodies within HL7. The FHIR Governance Board, appointed by the FHIR Technical Steering Committee provides the broad oversight of the standard. The FHIR Management Group, also appointed by the Technical Steering Committee, manage the day-to-day operations of the standard. Finally, he Modeling and Methodology Work Group handles the resource creation, guidelines and best practices.[4]

Why FHIR?

FHIR is HL7’s answer to the call for a new interoperability standard that could more easily be used on mobile and cloud-based applications and also speed the implementation process. These implementations can often be completed within a day or week vs. the traditional month or year-long implementation timeline.[1] FHIR is a needed update to the HL7 v. 2 but much less disruptive to workflows than v. 3. The specification is free and allows unrestricted use. FHIR uses the building-blocks of HL7 v. 2, 3 and CDA while improving the ease of use and flexibility to alter implementations as needed. The RESTful architecture is applied to web services to allow for easy transfer of resources between systems since they can be accessed through a uniform resource locator (URL). Due to this architecture, FHIR is well suited for mobile and cloud-based platforms. The RESTful API architecture also allows for transfer of data from one system to another without a need for the receiving system to know the structure of the API itself. This simplifies the interface between systems. (3) Once called to the receiving system, these individual resources can be extended and adapted based on individual implementation needs.[1]

The Fundamental Principles of FHIR[4]

        1)      Prioritize implementation
        2)	Provide a flexible framework for interoperability
        3)	Keep complexity where it belongs
        4)	Support but not mandate tight specifications
        5)	Leverage open source development principles
        6)	Free to use
        7)	Supports multiple exchange paradigms/architectures
        8)	Leverage common web technologies
        9)	Forward and backward compatibility
       10)	Tooling requirements are mainstream and minimal

FHIR Basics

Resources are classified as either clinical, administrative, or infrastructural. These resources were developed out of HL7 v.2 and v.3 (RIM) so these resources can coexist with previous HL7 standards. [1] These resources are accessed via a URL via specific web calls. Resources are represented in either XML or JSON format.

These resources have a related profile that specifies the resource’s metadata, associated structures of the resource, and relevant extensions used in the structures. The metadata contains a resource ID, version ID and the last modified date, in addition to other information. This metadata allows resources to be searched efficiently. In addition, metadata contains tags that can link a specific resource to a workflow event. This can be useful in establishing trigger events for initiating system interactions. Finally, resources can also be referenced to one another, via a resource link, which can connect various data elements. Resources are exchanged and manipulated via PUT, GET, POST, and DELETE operations via the individual APIs. Resources are queried by the receiving system or can be pushed from the host system.

Resource Classifications

Individual resources are contained within one of three primary categories and then sub-classified within each category.[1]

     1) Clinical
             a.	General
             b.	Medications
             c.	Diagnostic
             d.	Device Interactions
     2)	Administrative
             a.	Attribution
             b.	Entities
             c.	Workflow Management
             d.	Financial
     3)	Infrastructural
             a.	Support
             b.	Document Handling
             c.	Exchange
             d.	Conformance

FHIR enabled apps in use today

The SMART for Public Health Surveillance and Mass Gathering Preparedness is a collaboration between the Harvard Medical School and the ONC. SMART sought to develop a platform for the rapid development of health applications that could run across multiple EHRs. [5]They succeeded and now a variety of apps are “SMART-enabled”. The apps are used in clinical back-office settings, research, patient communication and patient facing applications.[6] FHIR is also gaining support in the U.K. Nearly ten apps have already been developed for use in various setting. Additionally, an alliance with the UK Renal Data Collaboration is planned.

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 FHIR DTSU v. 1.1. (2014). Retrieved October 21, 2014 from http://www.hl7.org/implement/standards/fhir/index.html
  2. Mckenzie, L. (2013, May 13)Introduction to FHIR. Retrieved October 20, 2014 from http://gforge.hl7.org/svn/fhir/trunk/presentations/2013-05 Tutorials/Introduction to FHIR.pptx
  3. (2013, Jan 16) What exactly is RESTful programming?. Retrieved October 23, 2014 from http://stackoverflow.com/questions/671118/what-exactly-is-restful-programming
  4. 4.0 4.1 HL7. (2014, Oct 22) FHIR Wiki. Retrieved October 23, 2014 from http://wiki.hl7.org/index.php?title=FHIR
  5. Raths, D. (2014). "Trend: standards development. Catching FHIR. A new HL7 draft standard may boost web services development in healthcare." Healthcare Inform 31(2): 13, 16.
  6. SMART. (2014). SMART-Enabled HIT. Accessed October 23, 2014 from http://smartplatforms.org/smart-enabled-hit/

Submitted by (Chris Hoekstra)