Diego, IMHO your contribution is orthogonal to what Thomas very accurately explained. Building subset is a symptom of the issue, not a solution.
As I tried to explain in my initial post, we are currently facing two generation of technologies in medicine: - systems that record information as trees of atomic concepts, in the same way we are all exchanging in "globish" by inserting English concepts in a grammatical structure, - systems that still rely on a fixed database schema and usually have a "discourse system" limited to field/value pairs. When I try to explain all this to lesser tech-savvy people (means, who don't belong to this list ;-) ), I usually explain that: - usual systems (with an information schema tied to a database schema) are like a printed form. The day after you received the 5000 printed sheet you ordered, you will realize that there are several design flaws that you will have to endure while the stock is not empty, - openEHR is a flexible schema, similar to a set of stamps that lets you build forms dynamically from blank paper. If your design has to evolve, you just have to adapt one of the stamps. - in my system, based on an ontology and a dependency grammar, you can use stamps (archetypes like) and/or "write" freely. I have always understood openEHR as a link, a step, between the "good old way" (discourse range hard coded into a database schema) and a modern approach where you can really "tell a patient story" using a genuine (structured, processable) language. 15 years ago, Thomas and I spent hours discussing the opportunity for openEHR to include a reference ontology in its kernel ; this decision was not made for very good reasons, but I guess that it still remains a necessary evolution. Thomas very accurately explained why SNOMED is a deceptive candidate for such a reference ontology. And, unfortunately, it is deep rooted in its origins as a coding system. I can hear all the arguments about "legacy system" and even "legacy medicine" (the one still fully organized for siloed acute care at a time our society already entered the information age and suffers from chronic diseases). The question remains to guess if SNOMED is a component that lets you stuck in the past or helps you disrupt the legacy craps. Now, let's imagine a modern system that would allow you to "tell a patient medical story" from the various viewpoints of a multidisciplinary patient centered team. What would be the point about having "local vocabulary subsets"? Do you think that a GP shouldn't use the word "mitral leak" or any other "specialized" word in the medical vocabulary? My feeling is that selected subset is a solution when using SNOMED as a coding system. The subset being the global list of values that are legal for the fields in the existing schema, in the same way you will select subsets in a billing system. But when it comes to "telling a story" using a language, in my opinion subsets are a non-sense. We don't use "vocabulary subsets" when we talk, and each contributor in a patient's team would mechanically get exposed to a super-set; subset is actually only fit for silos... and at a time when medicine is already becoming a narrow silo in health, I really don't see it as a sound strategy. Best, Philippe Le 23/03/2018 à 10:49, Diego Boscá a écrit : > IMO having both representations (pre and postcordinated) is not bad > per se (in fact, knowing that they are equivalent is pretty good). The > main problem is that technical people (including myself) shouldn't > just dump the entire snomed ct into a data field and call it a day. To > design better and useful systems you need a first "curation" phase > where you define your relevant subsets that fit your system. The > boundary problem is less of a problem if even if different terms were > used when the record was created we can assess that they are in fact > the same thing. > I think people are a little unaware of this step and causes problems > as the ones you and Thomas mentioned > > 2018-03-23 10:35 GMT+01:00 Bakke, Silje Ljosland > <[email protected] > <mailto:[email protected]>>: > > I read Thomas’ reply with great interest, and I generally agree > that with a well thought out information model, the very detailed > precoordinated expressions are redundant. At the same time I > understand Mikael’s point of view too. BUT, what I’m often met > with is that because these precoordinated expressions exist (like > for example “lying blood pressure” and “sitting blood pressure”), > we should use them INSTEAD OF using our clever information models > (that we do have) for recording new data. > > > > In my opinion this is wrong because it doesn’t take into account > that healthcare is unpredictable, and this makes recording more > difficult for the clinician. How many different variations would > you have to select from? Take the made up example “sitting > systolic blood pressure with a medium cuff on the left upper arm”; > this will be a lot of possible permutations, especially if you > take into account all the different permutations where one or more > variable isn’t relevant. > > > > So while I don’t think the existence of these precoordinated terms > in itself is a problem, it’s a potential problem that people get a > bit overzealous with them. > > > > Regards, > > *Silje* > > > > *From:*openEHR-technical > <[email protected] > <mailto:[email protected]>> *On Behalf > Of *Mikael Nyström > *Sent:* Friday, March 23, 2018 10:06 AM > *To:* For openEHR technical discussions > <[email protected] > <mailto:[email protected]>> > *Subject:* SV: SV: [Troll] Terminology bindings ... again > > > > Hi tom, > > > > I can agree with you that if SNOMED CT was created when all > patients in the world already had all information in their health > record recorded using cleverly built and structured information > models (like archetypes, templates and similar), but that is not > the case. Instead SNOMED CT also tries to help healthcare > organizations to do something better also with their already > recorded health record information, because that information to a > large extent still belongs to living patients. > > > > It would be interesting to have your opinion about why it is a > real problem with the “extra” pre-coordinated concepts in > SNOMED CT in general and not only for the use case of creating > archetypes or what would be nicest in theory. > > > > Regards > > Mikael > > > > > > *Från:*openEHR-technical > [mailto:[email protected] > <mailto:[email protected]>] *För *Thomas > Beale > *Skickat:* den 23 mars 2018 01:06 > *Till:* [email protected] > <mailto:[email protected]> > *Ämne:* Re: SV: [Troll] Terminology bindings ... again > > > > I have made some attempts to study the problem in the past, not > recently, so I don't know how much the content has changed in the > last 5 years. Two points come to mind: > > > > 1. the problem of a profusion of pre-coordinated and > post-coordinatable concepts during a *lexically-based choosing > process *(which is often just on a subset). > this can be simulated by the lexical search in any of the Snomed > search engines, as shown in the screen shots below. Now, the > returned list is just a bag of lexical matches, not a hierarchy. > But - it is clear from just the size of the list that it would > take time to even find the right one - usually there are several > matches, e.g. 'blood pressure (obs entity)', 'systemic blood > pressure', 'systolic blood pressure', 'sitting blood pressure', > 'stable blood pressure' and many more. > > I would contend (and have for years) that things like 'sitting > blood pressure', 'stable blood pressure', and 'blood pressure > unrecordable' are just wrong as atomic concepts, each with a > separate argument as to why. I won't go into any of them now. > Let's assume instead that the lexical search was done on a subset, > and that only observables and findings (why are there two?) show > up, and that the user clicks through 'blood pressure (observable > entity)', ignoring the 30 or more other concepts. Then the result > is a part of the hierarchy, see the final screenshot. I would have > a hard time building any ontology-based argument for even just > this one sub-tree, which breaks basic terminology rules such as > mutual exclusivity, collective exhaustiveness and so on. How would > the user choose from this? If they are recording systolic systemic > arterial BP, lying, do they choose 'systemic blood pressure', > 'arterial blood pressure', 'systolic blood pressure', 'lying blood > pressure', or something else. > > Most of these terms are pre-coordinated, and the problem would be > solved by treating the various factors such as patient position, > timing, mathematical function (instant, mean, etc), measurement > datum type (systolic, pulse, MAP etc), subsystem (systemic, > central venous etc) and so on as post-coordinatable elements that > can be attached in specific ways according to the ontological > description of measuring blood pressure on a body. This is what > the blood pressure archetype does, and we might argue that since > that is the model of capturing BP measurements (not an ontological > description of course), it is the starting point, and in fact the > user won't ever have to do the lexical choosing above. Now, to > achieve the coding that some people say they want, the archetype > authors would have the job of choosing the appropriate codes to > bind to the elements of the archetype. In theory it would be > possible to construct paths and/or expressions in the archetype > and bind one of the concepts from the list below to each one. To > do so we would need to add 40-50 bindings to that archetype. But > why? To what end? I am unclear just who would ever use any of > these terms. > > The terms that matter are: systemic, systolic/diastolic, terms for > body location, terms for body position, terms for exertion, terms > for mathematical function, and so on. These should all be > available separately, and be usable in combination, preferably via > information models like archetypes that put them together in the > appropriate way to express BP measurement. Actually creating > post-coordinated terms is not generally useful, beyond something > like 'systemic arterial systolic BP', or just 'systolic BP' for > short, because you are always going to treat things like exertion > and position separately (which is why these are consider 'patient > state' in openEHR), and you are usually going to ignore things > like cuff size and measurement location (things considered as > non-meaning modifying 'protocol' in openEHR). > > 2. similar *problems in the authoring phase*, i.e. addition of > concepts to the terminology in the first place. If more or less > any manner of pre-coordinated terms is allowed, with the > precoordinations cross-cutting numerous ontological aspects (i.e. > concept model attribute types), what rules can even be established > as to whether the next proposed concept goes in or not? It is very > easy to examine the BP hierarchy, and suggest dozens of new > pre-coordinated terms that would fit perfectly alongside the > arbitrary and incomprehensible set already there... > > (another 3x) > > > I've picked just the most obvious possible example. We can go and > look at 'substances' or 'reason for discharge' or hundreds of > other things, and find similar problems. I don't mind that all > these pre-coordinated concepts exist somewhere, but they should > not be in the primary hierarchies, which really, in my view should > look much more like an ontology, i.e. a description of reality > which provides a model of what it is possible to say. If that were > the case, the core would be much smaller, and the concept model > much larger than it is today. > > - thomas > > On 22/03/2018 00:26, [email protected] > <mailto:[email protected]> wrote: > > > > Hi Heather, > > > > In general, anyone is welcome to participate in the work; you > don't need to be one of the small number of Advisory Group > members. That helps with travel costs, but most of the real > work is done on teleconferences, not so much at the face to > face meetings. > > > > I would be very interested to hear people's articulations of > where they think the boundary should be for this boundary > line. I'd also be interested to understand better what people > think the problem is with having "extra" / unnecessary > pre-coordinated concepts; what advantage is to be gained from > removing them, and what is the perceived scale of the problem. > > > > michael > > > > > > -- > 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 > [email protected] > <mailto:[email protected]> > > http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org > > <http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org> > > > > > -- > > VeraTech for Health SL <https://htmlsig.com/t/000001C268PZ> > > Twitter <https://htmlsig.com/t/000001C47QQH> LinkedIn > <https://htmlsig.com/t/000001C4DPJG> Maps > <https://htmlsig.com/t/000001BZTWS7> > > Diego Boscá Tomás / Senior developer > [email protected]<mailto:[email protected]> > [email protected] <mailto:[email protected]> > > VeraTech for Health SL > +34 961071863 <tel:+34%20961%2007%2018%2063> / +34 627015023 > <tel:+34%20627%2001%2050%2023> > www.veratech.es <http://www.veratech.es/> > > Su dirección de correo electrónico junto a sus datos personales forman > parte de un fichero titularidad de VeraTech for Health SL (CIF > B98309511) cuya finalidad es la de mantener el contacto con usted. > Conforme a La Ley Orgánica 15/1999, usted puede ejercitar sus derechos > de acceso, rectificación, cancelación y, en su caso oposición, > enviando una solicitud por escrito a [email protected] > <mailto:[email protected]>. > > > > _______________________________________________ > openEHR-technical mailing list > [email protected] > http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org
_______________________________________________ openEHR-technical mailing list [email protected] http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org
