Health systems use numerous methods to exchange patient medical records, but providers continue to rely heavily on the old-fashioned approach of mail or fax, according to new federal data on interoperability.

Nearly three-quarters of non-federal acute care hospitals routinely use fax or mail to receive summary of care records from providers outside their system, according to new data released by the Office of the National Coordinator for Health IT. Two-thirds of health systems use fax or mail to send records.

Paper-based methods outpaced electronic transmission, particularly in receiving records. More than 4 in 10 systems said they “often” use mail or fax while 27% said they often use a standalone health information service provider like DirectTrust.

Centers for Medicare & Medicaid Services (CMS) Administrator Seema Verma has pushed the industry to adopt electronic methods for data exchange, calling on developers help “make every doctor’s office in America a fax free zone by 2020.”

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That will be a challenge given the industries reliance on the dated technology. Small, rural and critical access hospitals are a big driver behind the latest figures. There are wide gaps between participation in national data exchange networks among those providers and larger systems.

“These types of hospitals were about half as likely to routinely send and receive summary of care records using only electronic methods compared to their counterparts,” authors of the data brief wrote. “Instead, they largely relied on paper-based methods to routinely send and receive summary of care records with outside organizations.”

But hospitals also employ a wide variety of methods to exchange records. Nearly 80% of hospitals used more than one electronic method to send records in 2017. However, a quarter of hospitals are not receiving records electronically at all.

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Health information service providers were the most common form of electronic transaction followed by state or regional health information exchanges and EHR vendor networks. However, three in 10 hospitals still don’t participate in any national networks.

The number of methods used is a detriment to health systems, ONC concluded, adding that its Trusted Exchange Framework could help streamline those options.

“The number of exchange methods hospitals need to ensure that they have information electronically available and subsequently used, contributes to the complexity and costs of exchange,” the agency wrote. “These complexities and increased costs are often cited as barriers to interoperability. Efforts, such as the Trusted Exchange Framework, might help to simplify the exchange of health information through the use of health information networks.”