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Methods of Exchange of Health Information

  • Directed, or “push,” exchange.
    In directed exchange, information is sent and received electronically through direct secured messaging. Information can be sent in many formats, including basic notes, PDF-like attachments or standard message formats—such as ADT feeds and continuity of care documents (CCDs).
  • Query-based, or “pull,” exchange.
    In query-based exchange, patient information is searched for or requested, and then subsequently shared through standard message formats (such as ADT and CCD).

No single best practice defines the manner or method by which to achieve interoperable exchange of health information between providers. With the appropriate infrastructure, direct EHR-to-EHR exchange and exchange through facilitating entities provide similar information-sharing capabilities, but they can differ in administrative complexity, workflow integration, data aggregation capability and cost.

With the infusion of federal dollars to support exchange of health information and HIO development through the HITECH Act, many states have pursued HIOs as a vehicle by which to facilitate exchange of health information across health care providers and, in some cases, multi-provider or state-level data aggregation for reporting, research and analytics purposes. In 2015, the Robert Wood Johnson Foundation conducted a survey identifying the types of exchange efforts underway across the country.58The most commonly identified efforts were HIOs and state health information exchanges. (Note that HIOs are commonly referred to as “health information exchanges.”) Table 2 below provides an overview of exchange efforts currently underway.

Table 2: Health Information Exchange Efforts Underway in the United States59

Type of Organization
Health information organization
State health information exchange or state-designated entity
Health care delivery organization (e.g., hospital, integrated delivery network, individual practice association and ambulatory practice)
Community-based organization 11
Nongovernmental organization or policy/advocacy group 7
Public health department or agency 6
Technology vendor
State Medicaid agency 3
Academic institution 3
State government (other than state Medicaid or public health)


Previous infrastructure investments and the potential for population-based data aggregation and analysis that HIOs afford have made them an attractive prospect for many states. Even though they can add value to efforts to increase interoperable exchange of health information between providers, stand-alone HIOs face significant challenges related to their business model and long-term financial sustainability. The greatest challenge facing stand-alone HIOs, as opposed to those developed internally to an organization such as a health system or ACO, is that too few providers participate and subscription fees are intended to generate revenue. Providers often refrain from participation because they do not see the value in doing so, which may then result in gaps in clinical data that make HIO services even less appealing. In addition, because HIOs receive limited funds from provider sign-up and subscription fees, they often rely on grant funding as a primary source of revenue—an often unstable funding stream. Providers may not participate in HIOs because they do not believe it aligns with their business interests, particularly when balanced against other resource priorities more directly linked to revenue generation (for example, new inpatient facilities and well-reimbursed diagnostic tools).