Hi Heather, Comments inline below ...
Ian Dr Ian McNicoll office +44 (0)1536 414 994 fax +44 (0)1536 516317 mobile +44 (0)775 209 7859 skype ianmcnicoll ian.mcnicoll at oceaninformatics.com Clinical Modelling Consultant,?Ocean Informatics, UK openEHR Clinical Knowledge Editor www.openehr.org/knowledge Honorary Senior Research Associate, CHIME, UCL BCS Primary Health Care ?www.phcsg.org On 28 September 2011 02:01, Heather Leslie <heather.leslie at oceaninformatics.com> wrote: > Hi Ian, > > > > I'd be very interested to see the extent of these examples and make some > assessment whether an ordinal is the most appropriate way to model this > content. [IAN] I have only come across a couple of examples so far, the Walterlow Scle being the best example but mongst the many thousands of scales and scores out there, I bet there are other examples. > Few thoughts: > > ????????? The natural instinct is definitely to use an ordinal but is it > because of the layout/display in the requirements document or based on the > data itself? We could equally suggest that these values could be modelled as > a coded text list and assigned a value mapping in the same way you suggest. > [IAN] The requirement is to map a set of terms to a set of values. The ordinal is currently the only way we have of doing this. It could be argued that the Apgar and GCS are actually examples of mappings which happen to be ordinal. > ????????? Should the values simply be described, or actually assigned, in > the archetype (via the data type itself) and how much of this should be left > in the application GUI/workflow/logic? > [IAN] Wel,, yes. But surely the point of archetypes is to formally document as much of this knowledge as possible, rather than leaving it to application logic. I have managed to workaround the current restriction for the Waterlow Scale archetype but it is pretty counter-intuitive. The strength of the RM is that it should be rich enough to capture these sort of clinical ideas in a way that is clear ot both clinicians and developers. The idea of a termset mapped to numeric values is, I thikn, valid. The only issue is whether it makes sense to adapt the DV_ORDINAL for these non-unique uses-cases, or whether a new datatype is required > ????????? Is the clinical content reasonable - we have certainly found that > there are many instances of commonly used clinical content that is 'munged' > together for historical reasons, and that when we model, needs to be teased > out into subtlely difference concepts. That these values are directly > related or of similar granularity etc might need further discussion. > [IAN] I absolutely agree in principle but these requirements will come mostly from 'formal' scale and score instruments. Many of them will be poorly evidenced or only very locally used but we do not really have much choice but to model them 'as is'. > ????????? Or do we have a simple need to emulate the current practice > (rather than best practice/modelling) in the models, perpetuating any > historical practice without any further consideration? I recognise that > there is always a pragmatic argument for this too. > [IAN] I agree that there are areas where we are in as good position to define 'best practice' in information recording (and the discussions about 'severity' are a good example) but I do not think it is realistic for us to argue e.g. that the Waterlow Scale is 'wrong' because it does not fit our idea of a 'proper ordinal'. > > Cheers > > > > Heather > > > >>-----Original Message----- > >>From: openehr-clinical-bounces at openehr.org [mailto:openehr-clinical- > >>bounces at openehr.org] On Behalf Of Ian McNicoll > >>Sent: Tuesday, 27 September 2011 6:18 PM > >>To: For openEHR clinical discussions > >>Subject: Re: Multiple values in C_DV_ORDINAL constraints > >> > >>SPECR-72 posted > >>http://www.openehr.org/issues/browse/SPECPR-72 > >> > >>Dr Ian McNicoll > >>office +44 (0)1536 414 994 > >>fax +44 (0)1536 516317 > >>mobile +44 (0)775 209 7859 > >>skype ianmcnicoll > >>ian.mcnicoll at oceaninformatics.com > >> > >>Clinical Modelling Consultant,?Ocean Informatics, UK openEHR Clinical > >>Knowledge Editor www.openehr.org/knowledge Honorary Senior Research > >>Associate, CHIME, UCL BCS Primary Health Care ?www.phcsg.org > >> > >> > >> > >> > >>On 26 September 2011 20:42, Thomas Beale > >><thomas.beale at oceaninformatics.com> wrote: > >>> On 26/09/2011 18:22, Ian McNicoll wrote: > >>> > >>> I still cannot find the reference to the VCOV rule in the > >>> specifications - can someone point this out? > >>> > >>> I agree that we seem to be mixing up 2 somewhat different ideas here. > >>> One is the 'true' ordinal, where there is a set of ordered terms to > >>> each of which some sort of ordered but otherwise arbitrary integer > >>> value is assigned. If all we are doing is asserting the correct order > >>> of the terms then it is questionable whether anything other than the > >>> index position in the list is necessary e.g 0..n. However there are > >>> many examples of ordered lists in clinical use which have at least > >>> some sort of score attached to each list member. As Daniel has pointed > >>> out, it is somewhat dubious if these really qualify as ordinals and I > >>> agree with Tom's idea that these are really term->value mappings. > >>> > >>> I would vote for taking the simple option of removing the 'uniqueness' > >>> requirement. I doubt very much if this would cause any downstream > >>> problems with decision support, in that if unique constraints are > >>> required, these will be fully defined by the archetyping itself e.g a > >>> GCS or Apgar score. > >>> > >>> > >>> can someone please put an issue on the SPECPR tracker? It should quote > >>> this and Daniel's posts. > >>> > >>> - thomas > >>> > >>> > >>> _______________________________________________ > >>> openEHR-clinical mailing list > >>> openEHR-clinical at openehr.org > >>> http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-clinical > >>> > >> > >>_______________________________________________ > >>openEHR-clinical mailing list > >>openEHR-clinical at openehr.org > >>http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-clinical > > _______________________________________________ > openEHR-clinical mailing list > openEHR-clinical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-clinical >
