A softly-whispered rumor may soon be coming true: Evidence is mounting that the VA and DoD are gearing up to use 3M’s Health Data Dictionary as a cornerstone of the joint iEHR and, in turn, make it freely available to the industry.

Such a contribution, likened to Kaiser Permanente opening its Convergent Medical Terminology (CMT) in September 2010, is viewed by those interviewed for this story as potentially creating a de facto industry standard set of medical terminology with the potential to ultimately bolster interoperability in the U.S. and worldwide.

“We have agreed that we will use a common data definition between the VA and DoD and that’s just a critical piece in the data layer for us,” said VA CIO Roger Baker, during his monthly call with reporters on March 28. “So watch for that to play a pretty key role in what we’re doing.”

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While Baker did not name the open HDD by corporate brand during the call, he responded to an email inquiry by Government Health IT, and confirmed it is 3M’s HDD, which is essentially a relational database of health terminology.

In something of a thickening-plot twist, however, 3M “declined comment.” For transparency’s sake: No final, signed contract has been made public yet.

“Our agreement with DoD is that we will use an open version of the HDD,” Baker wrote. “I think your wording of ‘much like an open source component’ is correct.”

During the call, Baker described the iEHR architecture as consisting of four layers, a data layer, an enterprise services bus, the applications, and a graphical user interface, noting that when the VA deploys iEHR in two major hospital facilities within the next two years, three of those layers will be brand new; the exception, of course, is the applications.

Not only will the DoD and VA use 3M’s Health Data Dictionary as part of the iEHR data layer, but the agencies will also make it available via the Open Source Electronic Health Record Agent (OSEHRA) custodian that handles the open source aspects of iEHR.

“We hope that, by establishing standards for data and interfaces, making them publicly available, executing through the open source, and buying packages that meet the standards, we will encourage the community to use those standards more broadly than just the iEHR,” Baker wrote.

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As does Stan Huff, MD, and CMIO of Intermountain Healthcare, who pointed out that the open HDD is not a competitor or replacement for SNOMED CT, LOINC, or RxNorm.

“The HDD would have mappings from its internal codes to the standard codes,” Huff added. “The HDD does have a rich set of codes that are in practical use in several large health care systems, organized into very useful context specific code lists [value sets]. The combination of the rich content and the value sets makes the terminology services easy to implement.”

HDD being freely available and easy to implement means that health entities such as Intermountain can use it – but also, Huff noted, in addition to the DoD and VA, EHR and other HIT vendors might build upon it.

When presented with that possibility, Baker cut to the chase: “We hope so."

“I am of course pleased that the content will be effectively open source, it had been proprietary and that can never be a basis for a standard," said Christopher Chute, MD, who spearheads the Mayo Clinic’s bioinformatics division, chairs WHOs ICD-11 Revision Steering Group and whose research focuses on biomedical terminology and ontology.

The health vocabulary issue conceptually has two dimensions, Chute added: content, then syntax and services.

“Meaningful use has helped the former a lot, through the RxNorm, LOINC, and SNOMED CT triad – though of course that’s not the whole picture,” Chute continued. “The country, and arguably the world, needs practical subsets of these vocabularies which can plug into data quality metrics, clinical decision support algorithms, and generalized data elements.”

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Which is not to say that an open version of 3M's HDD will make that happen quickly, Chute and Huff agreed.

“My hope is that ONC and the [National Library of Medicine] will continue motions toward an open, interoperable set of content that are made available in standard syntax with standard services,” Chute said. “3M, along with others, would then be free to serve up such health vocabulary content, but I am not yet persuaded that the 3M content by itself will transform the industry overnight.”

With 18 million patients between them, the VA and DoD are recognized as a force that can move markets, and wielding that influence in the EHR and open source frays is bound to have an impact over the long run.

What’s more, the VA and DoD have made progress on the open source front of late, most recently appointing a board to oversee OSEHRA, and Baker said that the iEHR folks are fully involved with the utilization of open source.

“Our approach – of Va/DoD ‘landing’ on certain standards to help ensure their adoption – is working for us with the NwHIN,” Baker wrote, “and I could see the data and interface standards going the same route.”