LOINC, SNOMED-CT tighten medical coding integration

Two of the world’s most widely used medical coding standards will collaborate on a technology component that promises to provide a valuable link in health information exchange.

SNOMED International and the Regenstrief Institute, which oversees LOINC, have agreed to support more coordinated use of each other’s medical coding standards. The agreement includes a pledge to develop a LOINC extension that aligns with SNOMED CT and create an identifier for every concept that exists in both code sets. This will cut down on the duplication of content and make it easier for healthcare organizations to implement both coding standards.

“We want to provide a solution that meets both clinical and regulatory requirements globally,” Marjorie Rallins, executive director of LOINC Health Data Standards, said at this fall’s 2022 LOINC conference. “We believe our collaboration is transformative for interoperability, particularly as it relates to cross-border interoperation of information.”

Regenstrief will own and maintain the extension, and SNOMED will host it within its Community Content initiative. The two entities will also consolidate the committees and working groups associated with work on the extension, Rallins said.

“We are committed to making this particular collaboration and this new solution work, to taking it forward, and to making it successful,” Shelley Lipon, chief customer officer for SNOMED International, said at the same event.

Medical coding harmonization

Short for Logical Observation Identifiers Names and Codes, the LOINC standard includes about 100,000 terms to represent lab results, vital signs, and other measurable clinical elements. The Systemized Nomenclature of Medicine – Clinical Terms, or SNOMED CT, is an all-encompassing standard for clinical terminology that includes more than 350,000 terms. Both are widely used worldwide. In the United States, they’re required as part of Promoting Interoperability, the successor to meaningful use.

SNOMED and Regenstrief initially came together in 2013 and the following year released a reference set of nearly 12,000 LOINC terms that mapped to one or more SNOMED concepts. At the LOINC conference, Rallins cited three reasons for tighter collaboration:

• Adoption of the jointly produced map of common expressions was “minimal to modest.”
• Members of SNOMED want to include pathology in SNOMED-CT as part of the organization’s 2020-2025 strategic plan. This conflicts with the 2013 collaboration agreement, as pathology is at the core of the LOINC code set.
• LOINC has been criticized for lacking computable ontology. This makes it difficult to derive clinical meaning or otherwise interpret results from what’s stated by a single LOINC code.

A proof of concept for the LOINC extension is in the works and will be completed before the formal development effort begins, Rallins said. This development work will also include the creation of a computable ontology, Regenstrief said.

Calls for harmonization between the two medical coding standards date back to at least 2008. That year, a National Institutes of Health 2008 paper said efforts to automatically map lab procedures from LOINC to SNOMED CT were “incomplete and unsatisfactory.”

Brian Eastwood is a Boston-based writer with more than 10 years of experience covering healthcare IT and healthcare delivery. He also writes about enterprise IT, consumer technology, and corporate leadership.