What is Health Information Exchange?

An orientation for public health departments

The term "health information exchange" is sometimes used as a noun, and sometimes used as a verb. The following selections offer detailed information about the verb and noun functions of HIE.

Health Information Exchange (HIE) is used as a verb to describe "the electronic movement of health-related information among disparate organizations according to nationally recognized standards in an authorized and secure manner." HIE does not describe information movement solely within a single organization, nor a one-off idiosyncratic connection between two systems.

HIE (the verb) usually refers to real-time or near real-time exchange of information needed for clinical care, case management or public health purposes. This is distinct from moving information exclusively for billing and other administrative functions, known as electronic data interchange (EDI), or moving historical data for research and statistics. However, HIE services might also be used for these purposes.


At its simplest level, HIE requires the capability to "push" a message securely from one party to another. This is a post office-like function, sending a message or document - such as a laboratory result or an e-prescription - from one organization to another. This is also referred to as "direct," "point-to-point" or "transactional" exchange.

Some health information exchange organizations (HIOs) focus exclusively on "push" messaging, and do not support queries of unassembled information from multiple providers. Unfortunately, there is no universal term used to distinguish "push-only" HIOs, so the buyer must make the distinction.


A second, more sophisticated level of exchange builds on messaging, but also enables users to discover, assemble and "pull" information about one or more patients from various providers. "Pulling" can be used to assemble a longitudinal and comprehensive view of a patient's health history, similar to creating a "community" medical record department. This is sometimes called "query," "aggregate" or "community health record" exchange.

Health Information Exchange Organizations (HIO) are usually membership organizations that facilitate exchange between many different providers. Most members both contribute and receive information.

HIO members benefit from economies of scale, shared services and uniform participation agreements that simplify exchange, rather than each making such investments separately. For example, multiple laboratories can share one HIE solution to deliver results to many health departments, and the health departments can use one HIE solution to receive information from many labs.

Compared to mail, phone or fax, electronic HIE offers advantages of higher speed, lower labor and supply costs, and data encryption so unauthorized persons cannot read it. One profound advantage is the opportunity to import information directly into the receiver's information systems, rather than re-enter it by hand. Managed skillfully, this can reduce data-entry errors, speed recognition and delivery of urgent information, and improve workflow for routine tasks.

Such automated importing requires interoperability - that is, information is sent using data elements, vocabulary, formatting and transport standards recognized by computers on the receiving end.

Knowledge about all of a patient's diagnoses, treatments, allergies and preventive services across many providers, like that provided in "community health record" pull-type HIO functions, can be used to improve treatment while reducing expensive redundancies. Such information also facilitates public health case and outbreak investigation, care management and quality measurement, and supports studying the patterns of incidence, care and modifiers of health and injury in the community.

Depending upon the types of information shared, these message and query processes can be combined in an enormous number of ways to meet a wide range of needs, including but not limited to:

  • delivering a diagnostic test result or case report
  • delivering immunization data to an immunization information system
  • reviewing records for outbreak investigations
  • performing population health surveillance
  • alerting providers of opportunities to improve a patient's care (often called clinical decision support)

HIE typically refers to information exchange between healthcare providers, but patients' ability to View, Download and Transmit (VDT) their own records using Blue Button standards (and supported in Meaningful Use regulations) offers a new twist. Patient-mediated exchange may provide an alternate pathway for HIE, and because the exchange is patient-driven, it can obviate some of the privacy and confidentiality concerns of inter-provider exchange.

The simplest "push" messaging HIE process does not require a sophisticated HIO. Two professionals could send each other health information using relatively simple secure messaging protocols, such as DIRECT encrypted email, if they know one another's secure email addresses and can exchange the necessary decryption keys.

However, because of the large number of entities that seek to communicate from time to time (e.g., doctors, hospitals, pharmacies, labs and now even patients), it rapidly becomes impractical for each to establish one-on-one communications with all possible exchange partners. Nor does such simple messaging allow for more sophisticated exchange, such as "pulling" and integrating information about one patient from multiple providers simultaneously. This is where the Health Information Exchange Organization (HIO) may come in to provide these more complex exchange services.

HIE-Contrasting Direct Messaging with HIO Exchange II

Members typically use their own electronic systems to connect to an HIO. For instance:

  • Healthcare providers use their Electronic Health Record (EHR) systems
  • Laboratories use their Laboratory Information Systems (LIS)
  • Health departments use their surveillance and registry systems, as well as EHR systems

Additionally, HIOs frequently provide secure Internet websites, called portals, to view exchange information for those unable to import information into their own systems.

EHR vendors are starting to offer cumulative "pull" views of patient data from across many different customers of their systems, as well as building DIRECT exchange capabilities directly into their products. Thus the line between EHR vendors and HIOs is becoming increasingly blurred, and although information exchange with users of other vendors' products may be limited, some are becoming powerful HIOs in their own right (see HIE Organization Types).

However, as long as diverse organizations want to use diverse software applications - in other words, many "brands" of EHRs and other software - to communicate with one another, the need for some kind of vendor-neutral information exchange standards and brokers will exist indefinitely.

Information Partners Are Key

For all the advantages that HIE has to offer, the benefit of HIE comes from being connected, not from acquiring technology. No matter how elegant the technology an HIO might offer, it will not add value if the health department's frequent information sharing partners, or trading partners, are not members.

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