Hi Tom, I believe that you proposal to ”move / remove the pre-coordinated codes out of SNOMED” is very appealing in theory. However it is very difficult in reality to agree on where the line between a suitable pre-coordinated concept and a concept that is better to post-coordinate or handle in another way are. The line between the two alternatives also seem to be use case dependent, which makes it even more difficult, and of cause also related to the boundary problem. However, until there is a strong agreement on where the line should be I continue to believe that it is better so include the concepts in the same pile and let each use case decide how to select the concepts they need and transform between the different representations.
I like discussions about SNOMED CT and I don’t have any problems at all with critical comments as long as they are fair. Those kinds of criticism quite often makes me writing change requests. I am also happy to answer questions about SNOMED CT. However, I and several other people that are involved in the SNOMED CT community are quite tired of people that argue that SNOMED CT is bad based on incorrect facts and/or SNOMED CT is bad because it isn’t optimized for their narrow use case. Regards Mikael Från: openEHR-technical [mailto:openehr-technical-boun...@lists.openehr.org] För Thomas Beale Skickat: den 21 mars 2018 14:17 Till: openehr-technical@lists.openehr.org Ämne: Re: SV: [Troll] Terminology bindings ... again Nevertheless, I think it would have been good to move / remove the pre-coordinated codes out of SNOMED, and leave a pure post-coordinatable core, which would actually look a lot more like Philippe's (much smaller) terminology. This relates to the old debate on reference v interface terminology, and just throwing out precoord concepts is probably not right - they need to be in a completely different hierarchy. The post-coordination grammar in SCT is good, its theoretical challenge is the concept meta-model, i.e. what things like 'morphology', 'laterality' you can mention, and in what relationship. But this is hard for all of us, and requires some serious ontology work (Mikael and other experts know all about this of course). What I would say is this: in a similar way that I think SNOMED should have separated out 'SNOMED technology' (representation, APIs etc) from content, I think the concept meta-model should have been / could be made a separate artefact, maybe even an OBO ontology - at the moment it is too hidden inside the giant content artefact. If that were done, we could work more effectively on aligning with information / content models, whose attribute names should, generally speaking relate to (or be the same as) the meta-model ontology entities. If we pursued this line, the ontology would instantly be expanded by examination of archetypes, and conversely, many archetypes could be fixed where they contain errors or questionable attribute names. THis isn't to criticise experts or work done in SNOMED per se, but we should be perfectly happy to critique SNOMED, as long as that critique is collegial, and above all intelligent. (BTW maybe Philippe was not entirely diplomatic, but he did implement a very nice post-coordinating terminology and clinical noting system, so he knows a thing or two). So in that sense, I stand by my earlier comments that it would have helped (and still would help) if SNOMED International would consider some of my suggestions on separation of technology from content, separate the meta-model, and also a more serious effort to help connect terminology to information models / content models. We are slowly solving this on our side, but strategic cooperation would be better. One thing is clear: terminology is not a standalone proposition. - thomas On 21/03/2018 13:48, Mikael Nyström wrote: Hi Philippe, I think that you have missed that SNOMED CT is created for multiple use cases. Your use case that you describe as "a modern approach" is a good use case that I like. In that use case SNOMED CT can be used in the way you describe using SNOMED CT's concepts a little higher up in the hierarchies together with SNOMED CT Compositional Grammar and SNOMED CT's concept model. Another use case, that many implementers consider is important but you don't seem to care about, is the ability to handle legacy data to be able to keep a life-long health record. Most people alive today where born when simple health records that only used simple coding where in massive use. (When that era started and (potentially) ended is up to the reader to decide...) To cater for information that are more of legacy information, SNOMED CT also has concepts that can represent that kind of information. But SNOMED CT also has a machinery to transform between the different representations. Your example "fracture of the left ankle" is not possible to express using a single concept from SNOMED CT, but if it had been possible it had been possible to automatically transform that concept to the expression below, which seems like to be what you argue for in your "modern approach" use case. 64572001 | Disease (disorder) | : { 363698007 |Finding site| = {33696004 |Bone structure of ankle (body structure)| : 272741003 |Laterality| = 7771000 |Left (qualifier value)|}, 116676008 |Associated morphology| = 72704001 |Fracture (morphologic abnormality)| } I therefore find your arguments against SNOMED CT equally relevant as arguments of the type "SNOMED CT is useless, because it contains the concepts 285336007 | Background radiation (physical force) |, 60638008 | Planetary surface craft, device (physical object) | and 242250006 | Crash landing of spacecraft (event) | and I don't need that kind of concepts at my clinic." because the simple solution is to not use what you don't need. Regards Mikael -- Thomas Beale Principal, Ars Semantica<http://www.arssemantica.com> Consultant, ABD Team, Intermountain Healthcare<https://intermountainhealthcare.org/> Management Board, Specifications Program Lead, openEHR Foundation<http://www.openehr.org> Chartered IT Professional Fellow, BCS, British Computer Society<http://www.bcs.org/category/6044> Health IT blog<http://wolandscat.net/> | Culture blog<http://wolandsothercat.net/>
_______________________________________________ openEHR-technical mailing list openEHR-technical@lists.openehr.org http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org