Like previous versions of FHIR, Release 4 lets data travel in discrete pieces. The new version also includes additional stability for several of the standard's elements. Because those elements are now mature enough to remain stable, that means that developers will have less difficulty using them.
"What it promises is backward compatibility," HL7 CEO Dr. Charles Jaffe said. "This is really important both from an interoperability perspective and a financial one, because you don't want to be developing products that will not be compatible with future updates."
If developers build a tool based on those elements today, when the next FHIR version is released, the tool they built will still work.
"In practice, that means that developers can be much more confident in using certain parts of FHIR, because they're not going to change," said Nick Hatt, senior developer for Redox, an interoperability-focused software company.
Among those parts is a modern, web-based application programming interface that developers can leverage to make tools for sharing and accessing health data. The API is already used in other industries.
In healthcare, APIs have become more and more crucial, with developers using them to open up access to patient data. For instance, Apple offers an API to let developers tap into health data patients have downloaded onto their iPhones via the Health app. That download is possible thanks to FHIR, which stands for Fast Healthcare Interoperability Resources.
The new FHIR release "is a promise to provide reusable data across the continuum of biomedical research, patient care and population health," Jaffe said in a statement.
According to the Office of the National Coordinator for Health Information Technology, FHIR has finally started to catch on and many developers use the standard. Most hospitals and Merit-based Incentive Payment System-eligible clinicians who use federally certified health IT products have software from vendors that support FHIR, according to the ONC.
The federal government has been using the standard too. The CMS' Blue Button 2.0 uses FHIR to let beneficiaries bring their claims data into third-party apps and services.
It remains to be seen how the CMS' other initiative on patient data-sharing, MyHealthEData, will depend on FHIR.
There are still limitations to FHIR. At this point, only a few of the core elements are considered normative, Hatt pointed out.
HL7 has been in the standards game since 1987 and now has about 500 corporate members, including the majority of healthcare IT vendors. The organization published its first draft standard of FHIR in 2014. With this release now available, the organization will focus on the next version, in which the organization intends to make more parts backward-compatible.