2012-10-02 V3 Datatypes Task Force

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Scope and mandate of this group: Need a recommendation for the V3 Modeling to the TSC.

Occurs every Tuesday effective 9/25/2012 until 11/27/2012 from 1:00 PM to 2:00 PM.

TSC concall coordinates Dial 770-657-9270 and enter pass code 985371#

Co-chairs: Woody, Charlie
Today's Chair: Woody


  • Hugh Glover - present
  • Paul Knapp - present
  • Austin Kreisler - present
  • Lloyd McKenzie - present
  • Ron Parker - present
  • John Quinn
  • Pat van Dyke - present
  • Mead Walker - Mead
Scribe: Lynn Laakso

past meeting notes:


Solicit an existing commercial versioning and sunsetting strategy and adjust, test against our Datatypes problem.

Charlie describes Oracle's strategy. HL7's Datatypes issue is example of larger versioning strategy.

Is 1.1 a straddling step. Straddling indicates there's a way to migrate from a to b. 2b and 1.1 give you a fork and interoperate with 1.0 poorly to straddle for SPL environment Paul relates 1.1 as "1.4", and 2b as "1.6". Interoperation will cause 'breakage'.

Paul moves and Charlie seconds approval of the 2012-09-12 minutes. Unanimously approved.

Charlie moves and Lloyd seconds approval of the 2012-09-25 minutes. Unanimously approved.

Last Week's Action Items:

  • Hugh has exchanged emails with John Hatem but doesn't have anything to share yet. We are not likely to get a document from them, just narrative of experience.
  • Lynn to check with Don on his draft guidelines for versioning for Publishing. Woody shows package note to readers on ballot site in section 5.2.2 for what V3 was trying to do. We can try to pull this out to circulate as a Word document for people to use. There is also definition of substantive change. Those are the principles followed in Harmonization. He notes the section on 5.2.2 where a message structure may be declared obsolescent. This was declared obsolescence and replacement, with a time period of four years.

Hugh notes there's no argument that there was a process followed, and people knew there would be changes. This is a specific community of interest holding great influence, wanting to sustain a change declared obsolescent. Need to decide as a principle if we're prepared to meet that request and develop a mechanism to sustain the obsolete.

Charlie notes that the task of the group bigger than datatypes issue, to look at other frameworks.

Action Items:

  • Charlie to write his narrative of Oracle's versioning strategy for reference.
  • Woody asks Hugh to write up the choices as he sees them. Lloyd notes that V2, V2, and FHIR have different sets of principles. CDA has an extension mechanism. CDA R2 to R3 is stacking transforms. Each product line has different choices made around wire format backwards compatibility.

Austin notes that we need to show the Board how expensive such a change will be. Hugh asks if we can develop an exception mechanism or does all of V3 have to become wire-format backward compatible.

Product Line principles:

  • CDA Principles - R1-R2 ; R2-R3 (Austin)
  • FHIR Principles - evolving but more rigid than V3 (Lloyd) - see attachment
  • V2 Compatibility - obtain from Chapter 2 (Mead) - see attachment
  • V3 Principles - located as above

Lloyd asks for a recurring calendar entry with the new GTM that Woody sets up.

Board Resolution - strictly wire-format statement that ignores the need to evolve within a product.

Adjourned 2:06 PM EDT