Thomas My approach to this, which is expressed in the editor, is to standardise only on the base and maximum values of the ordinal. The terms that are used are not an issue and standardisation is really way beyond scope when people use all sorts of terms for this purpose. Apgar is a classic - 0,1,2 is quite clear - how these points are described varies enormously - but that is OK. Nurses may want something different than doctors - for example. It is the tightly defined context that is important and the fact that it is ordered. This does allow comparisons and normal values to be determined.
So, Urinalysis - NORMAL can be something that an archetype can express. Blood = 0, Protein = 0 ... You are always worried about the non-standardisation but we do not need it in this world to make interoperability a reality - ordinal values are, on the whole, too gross for a great deal of concern. Reflex of +/- can be normal if the person is healthy and the finding is consistent. Sam > -----Original Message----- > From: owner-openehr-technical at openehr.org > [mailto:owner-openehr-technical at openehr.org]On Behalf Of Thomas Beale > Sent: Friday, 24 October 2003 6:22 PM > To: Openehr-Technical > Subject: Re: Pathology requirements TEXTURAL RESULTS TO QUANTITIES > > > > Tim Churches wrote: > > > Sam Heard <sam.heard at bigpond.com> wrote: > > > > > > TEXTURAL RESULTS TO QUANTITIES > > > > ?TEXTUAL? > > > > This raises the general issue of how mixed categorical/ordinal/scalar > quantities > > are handled eg (made up example) haematuria: Trace->x RBC/ml -> Gross > > haematuria. Conceivably some use might be made of the numbers, > as opposed > > to the ordinal categorical extrema? > > The current DV_ORDINAL data type consists of an integer value > representing the > ordinal position in a range of values, and a symbol, which is the > symbol given > to that position. Ordinals are treated as being comparable (< operator is > defined) but not quantified (the magnitude is unknown). We currently think > that the correct way to express the symbol is as a term in a > vocabulary (maybe > subsetted). This means that each set of symbols comes from its own > micro-vocabulary, and even if the same symbols (like "trace", > "+", "++") are > used for unrelated things, they cannot get mixed up in comparisons. > > Examles: > > pain: > Value Symbol > 1 + > 2 ++ > 3 +++ > > reflex > Value Symbol > 1 + > 2 ++ > 3 +++ > > haemolysed blood in urinalysis > 1 ?neg? > 2 ?trace? > 3 ?small? > 4 ?moderate? > 5 ?large? > > OR - haemolysed blood in urinalysis (unit=cells/ml) > 1 ?neg? > 2 ?trace (10)" > 3 ?small (<25)" > 4 ?moderate (<80)" > 5 ?large (>200)" > > I am not sure if we need more sophistication to deal with this. The main > problem I see is the lack of vocabularies, and/or > non-standardisation of them. > I guess LOINC has the kinds of values we want, but how to specify > the correct > subsets? > > - thomas beale > > - > If you have any questions about using this list, > please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
