One thing I've learned in the government is that words matter, and sometimes, particularly in complicated or technical areas, it can be hard to use words that are precise and accurate. Sometimes we use the same term to apply to a broad range of concepts or ideas because it can be complicated to describe all the nuances captured by that work. Sometimes the words we use start out as verbs and then turn into nouns. Sometimes the names (and meanings) evolve over time. And sometimes the same words are used in different areas to mean entirely different things.

For example, the words "interoperability" and "health information exchange" are two words that we often use interchangeably, but I think it's important to realize that they are not the same thing.  Search results for the term "interoperability" will get you millions of hits, and generally include concepts of standardization, integration, cooperation and technical specifications. 

Defining interoperability

For definitions of technical interoperability, my favorite definition comes from the Institute for Electrical and Electronics Engineering. IEEE (eye triple-E) is the largest professional organization of geeks out there. And they have been dealing with the issue of interoperability for a very long time.

The IEEE Standard Computer Dictionary defines interoperability as "the ability of two or more systems or components to exchange information and to use the information that has been exchanged." See IEEE Standard Computer Dictionary: A Compilation of IEEE Standard Computer Glossaries.

That means there are two parts to the definition of interoperability: The ability of two or more systems to exchange information and the ability of those systems to use the information that has been exchanged.

This means that health information exchange is different than health information interoperability. Exchange is necessary for interoperability, but it is not sufficient by itself to achieve health information interoperability.

Defining the difference 

Because exchange is a prerequisite for interoperability, here at ONC we've focused a lot of attention on it. Our early work with the NwHIN pilots emphasized secure, query-based exchange (using something called Web Services) in which one system asked (or queried) another system for information. The DIRECT project defined a secure, email-based exchange system in which one system pushed information to another system. And both Web-services and email-based exchange are part of the 2014 edition of the certification rule that we issued last August.

But we must always remember that exchange is only part of the puzzle. If I send an email from one computer to another computer, I have exchanged information between those two systems. But if I write my message in French, (and you can only speak English), there is no way for you to automatically use the information that has been exchanged without risking losing something in translation. Similarly, if I use DIRECT to send a scanned office visit report from one EHR to another EHR, I may have exchanged information, but I won't be able to seamlessly use the information in the new system to alert the provider automatically of a new drug allergy, for example. So to get to health information interoperability, we need more than just transport standards:  We must also use standards for vocabularies and terminologies (to help standardize the meaning of the words that we use), standards for structure (so computers know how to break a message into the appropriate information chunks), and potentially other kinds of standards. 

Health information exchange is important  -  it is a vital part of modernizing our healthcare system. But health information exchange is not the same as health information interoperability. Transport standards are important to achieving health information exchange, but they will not get us to true interoperability unless we continue our work developing the full set of standards needed to support interoperability.

Doug Fridsma, MD, is chief science officer and director, Office of Science & Technology within the Office of the National Coordinator (ONC).