Thomas, I agree.
In the Semantic Stack various layers are orthogonal and intersect. The intersection between SNOMED Reference Terminologies and structures (archetypes) is exactly at the righthand side of the ‘is’ relation. Codes from SNOMED are ‘universals’, meaning definitions, like entries in a dictionary. They define generic truth’s. Archetypes are Logical Models that define what will be documented about a specific patient by a specific author at a specific place and time, for a specific reason. The nodes in the structure are needed to document the data in its context, the epistemology. Archetypes are about ‘particulars’. They are the left-hand side of the ‘is’ relation. This left-hand needs a different code from a different coding system. LOINC is the logical candidate. Even without a filled right-hand side with a SNOMED code, there is the need to bind a code to the left-hand side in the archetype to disambiguate it. Two kinds of coding systems intersect in the Semantic Stack layer that is the Archetype in well defined locations for well defined reasons. Gerard > On 3 sep. 2016, at 08:51, Thomas Beale <thomas.be...@openehr.org> wrote: > > > > On 02/09/2016 04:04, Bert Verhees wrote: >> On 02-09-16 11:18, Daniel Karlsson wrote: >>> Terminologies typically do not specify which pieces of information are >>> needed in a given situation. >> >> Hi Daniel, I don't have at the moment opportunity to reply to all you write, >> so excuse me for cherrypicking one idea of your message. >> >> I thought SNOMED specifies which information is needed in a given situation, >> but maybe I misunderstand you? > > It does various things, but this is not one of them, except by accident ;-) > > SNOMED is on the right-hand (ontological) side of the is-about relation, EHR > information (defined by archetypes) is on the left (epistemological) side. > > So terminology codes within EHR information can indicate what the items 'are > about' (in terms of real world categories) but the structures and data types > of information items are not generally known within the terminology. > Terminology doesn't say why pulse is a good surrogate for heart rate, or in > what circumstances MAP BP would be used, or the structure of data in a liver > function test. These are generally contingent relations and substitutions, > based on cultural, economic and other factors. Terminologies (if well > defined) mostly deal in necessary / invariant relations between entities. At > the next level out, EHR data relates to situations, which are full of > accidental relationships; terminology doesn't easily deal with these either. > > - thomas > > > _______________________________________________ > openEHR-clinical mailing list > openEHR-clinical@lists.openehr.org > http://lists.openehr.org/mailman/listinfo/openehr-clinical_lists.openehr.org _______________________________________________ openEHR-clinical mailing list openEHR-clinical@lists.openehr.org http://lists.openehr.org/mailman/listinfo/openehr-clinical_lists.openehr.org
