Dear all,
A new proposed draft of the openEHR data types is available at
http://www.deepthought.com.au/health/openEHR/data_types_1_5_2.pdf. This
draft includes a major rewrite of the explanation of text types (plain
text, coded text and friends). The model is not drastically different,
apart from the addition of a new attribute in DV_TEXT called mappings.
This is an important attribute, as explained in the text, and covers the
semantics of classifying terms, equivalents (HL7 "translations"), and
other scenarios where text (coded or otherwise) is mapped to other terms.
OPEN QUESTIONs
There are a few outstanding questions on the model, which terminology
experts on this list might like to respond to.
1. The use of rubrics in TERM_REFERENCE and DV_CODED_TEXT.
The "rubric" is the textual rendering corresponding to a code. We have
put it in TERM_REFERENCE, which models exactly the 1:1 asscociation of a
rubric and a code, and also in DV_CODED_TEXT, where it means the final
text string generated by the terminology service, taking into account
qualifiers. For almost all instances of DV_CODED_TEXT, there is only one
TERM_REFERENCE anyway, so the two rubrics are duplicates. For those
cases where post-coordination of a primary and one or more qualifiers is
generated by the terminology service (e.g "lung, left"), the rubric of
each TERM_REFERENCE will be the primary and the qualifier terms ("lung"
and "left", respectively), while the rubric of the DV_CODED_TEXT the
coordinated result ("lung, left").
Sam Heard suggests that there is no reason to keep the rubrics of the
TERM_REFERENCEs, since a) it is almost always a duplicated of the rubric
of the DV_CODED_TEXT, and b) it will never be needed even in cases where
qualifiers are used.
Is there any reason to keep TERM_REFERENCE.rubric?
2. Mode-changing term flag
We have not currently used a flag to indicate change of mode such as
"risk of", "history of" etc. Our analysis is that the proper use of
archtyped information structures obviates the need for any such special
indicator.
Dipak Kalra and David Lloyd (and I suspect many others) argue that such
a flag or indicator is still needed.
Are there other opinions on this matter?
3. Negation flag
Simiarly, we don't believe that any special flag is needed for negation,
and in fact is likely to be dangerous.
We know however that many might not agree, since almost all of us are
used to the "old" world in which EHR data was not constructed according
to well-defined models. Are there any arguments for adding a flag to
indicate negation to the DV_CODED_TEXT class - with evidence and
examples please. Please read the arguments in the document first, before
replying!
- thomas beale
-
If you have any questions about using this list,
please send a message to d.lloyd at openehr.org
