for me, conversion between different units that are comparable. You should ask Tom what else he thinks it yields up. I'd be interested.
Grahame On Mon, Mar 19, 2012 at 11:06 AM, <Michael.Lawley at csiro.au> wrote: > > Graham, > > I'm trying to make sense of this discussion around "computability" -- what > are the kinds of things that one wants to "compute" with these kinds of > countable things? > > michael > > On 18/03/12 10:57 PM, "Grahame Grieve" > <grahame at healthintersections.com.au> wrote: > >>Are discrete units only encountered in administrative directives? Do >>you prohibit people from making observations or measurements that >>include discrete units such as puffs, tablets, patches, vials, strips etc? >> >>why? >> >>HL7 does because we claim that you have to have UCUM codes >>so the data can be computable. If people simply want to exchange >>it in a structured but non-computable fashion... they can go to hell. >>And as for computable: we insist on a ucum code, and then say >>that for these discrete unit kind of things, well, you just put "1" for >>countable units, and then put the effective unit somewhere else - >>somewhere that no one can actually pull off in practice - because >>this is more "computable". Huh? We do not make sense on this. >> >>So much for HL7... what's openEHR's excuse? >> >>Grahame >> >> >>On Sun, Mar 18, 2012 at 11:18 PM, Thomas Beale >><thomas.beale at oceaninformatics.com> wrote: >>> >>> As Grahame mentioned on an earlier post, the question of units is >>>thorny. >>> Although we technical people would like to mandate UCUM or some other >>> well-designed computable syntax, on its own, it won't work. There seem >>>to be >>> two reasons for this: >>> >>> it doesn't take care of the need for a displayable form of units, e.g. >>>the >>> computable form 'mcg' or 'ug', where as the displayable is '?g' (Greek >>>mu >>> followed by 'g') >>> it doesn't take care of 'units' like puffs, tablets, patches, vials, >>>strips, >>> and other discrete delivery units >>> it doesn't take care of discrete delivery units per time, e.g. '2 puffs >>>/ >>> hour' >>> >>> Grahame and others have already done a lot of thinking on this here - >>>there >>> are a lot of excellent examples from Linda Bird on the Singapore >>>programme. >>> >>> The more I think about the last two above, the more I think it is not >>>about >>> quantities per se but about an administration directive (how the patient >>> should take something). Trying to make Quantity do that kind of stuff >>> doesn't make sense to me - there is obviously a Quantity to indicate the >>> dose in scientific form, but another data element may be needed to >>>indicate >>> how (in what discrete measures) to take the medication. >>> >>> I would therefore expect a distinct data element in the Medication >>>Cluster >>> archetype rather than a re-engineered Quantity type to deal with these >>>last >>> two. For the first one - displayable v computable, we will need a CR to >>> change DV_QUANTITY, and make it work like the FHIR Quantity - i.e. have >>>a >>> second units field. >>> >>> Some of my earlier thoughts are actually on the above wiki page - the >>> concept of a DiscretisedQuantity type inheriting from Quantity, which I >>> think is also a reasonable alternative. >>> >>> what do others think? >>> >>> - thomas >>> >>> _______________________________________________ >>> openEHR-technical mailing list >>> openEHR-technical at lists.openehr.org >>> >>>http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr >>>.org >> >> >> >>-- >>----- >>http://www.healthintersections.com.au / >>grahame at healthintersections.com.au / +61 411 867 065 >> >>_______________________________________________ >>openEHR-technical mailing list >>openEHR-technical at lists.openehr.org >>http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr. >>org > > > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at lists.openehr.org > http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org -- ----- http://www.healthintersections.com.au / grahame at healthintersections.com.au / +61 411 867 065
