Proposed Refinements to Axis Naming Conventions

As we are working to harmonize existing LOINC codes with the new axis values, I’ve identified 2 areas where I’d like to propose tweaks to the axis values as they currently appear (see LOINC Users’ Guide from July 2008). These are basically editorial changes, but thought it would be good to open for comment.



Use “and” everywhere in the SMD instead of “&”.


  • In radiology, combine multiple images with different views with &. Systems that encompass multiple organ systems are combined with +.[/*:pw2yi0bv]
  • Using & makes it somewhat harder to distinguish from +, which we will intentionally use when we want to specifically combine values from within an axis[/*:pw2yi0bv]
  • Couldn't find an example where "&" was not interchangable with "and".[/*:pw2yi0bv]
  • Has the benefit of working better in RELMA searches - & gets removed.


Using (.) dot separators in Role

  • There was general agreement that this is probably the preferred approach. Is consistent with the convention elsewhere in clinical LOINC where the dot signifies a sub-category.

  • Some seem to work better than others:
    o Physcian.attending
    o Physician.fellow
    o Interdisciplinary.team
    o Nursing.clinical nurse specialist
    o Nursing.nurse practitioner
    o Nursing.CRNA

  • Some challenge with whether to capitalize the second thing or not. We have tended not to elsewhere.

  • Existing terms highlight some things that need to be migrated to Component (SMD)
    o Nurse.surgery - > Nursing (with Surgery as SMD)
    o Nurse.general medicine -> Nursing (with General Medicine as SMD)


Comments and other feedback welcome.

An alternative to using a dot separator in Role would be to flatten the list out, making a determination about whether to include the parent node in the name or not. For example, “Team” could probably stand on its own, as perhaps the nursing sub-categories could, but we would need something like “attending physician”, and “fellow physician” (though that sounds weird). I personally prefer the dot.

I am for making use of and/& consistent throughout the axis terms, and while I could otherwise go with either, I think to be consistent with other LOINC’s that “and” should be used.



Before I address the dot operator, I just want to point out that currently the SMD axis term would not go in the Component axis. As titles are modeled in 2.24, Role and SMD appear together in Method.



It seems to me that the only Roles requiring a greater specification than the simple leaf terms are under the node of Physician. I furthermore think that they only sound awkward should they appear alone in the Method, i.e., when no SMD is specified. But when an SMD is specified, I think that the leaf terms sound appropriate on their own. As we currently see the Method axis modeled as SMD.Role, we would have, for example, Surgery.Attending or Cardiology.Fellow or Oral Surgery.Resident or General Medicine.Intern. Without an SMD, the Method could appear as Physician.Attending or Physician.Fellow or Physician.Resident or Physician.Intern.