Re: poor version management in archetype editor / clinicians content

[Thomas Beale <thomas.beale@oceaninformatics.com>]

Williamtfgoossen@cs.com wrote:
> In a message dated 3-12-2008 14:57:33 W. Europe Standard Time, 
> thomas.beale@oceaninformatics.com writes:
> > I still don't quite get
> > what way DCM is going - I thought it was going with archetypes, based on
> > the meeting a year ago, but in any case, I think the job of
> > standardising clinical models must be done by clinical people, and on a
> > far more agile basis than any of the official standards organisations.
>
>
> DCM is about standardising clinical models done by clinicians. 
> Archetypes are one way to go (if certain conditions are met, see 
> discussions). Other models will remain for a while. Core of DCM is 
> either UML and from there to archetype or to HL7 v3 XML, or transforms.

Hm...you will definitely run into problems with UML, due to the 
weaknesses around constraints in general, and also the orientation to 
class models rather than object models. They have never really worked 
well so far in health and I don't expect them to in the future. They do 
give an illusion of working in some simplistic and very controlled 
circumstances but in general they won't go the distance. But I am much 
more interested to get a definitive list of limitations you see in the 
archetype formalism (not the current tools). I went back through the 
posts on this list,  but still don't have a clear picture of the 
requirements you think archetypes don't meet.

With respect to invariants (which I would propose to rename 'rules'), 
the current ADL 1.5 spec includes a draft of new facilities (see section 
6 of 
http://www.openehr.org/wiki/download/attachments/196633/adl_1.5.pdf) 
which is more powerful than it was, and will allow any kind of formulas. 
The exact syntax is still being decided, but it may well end up being 
Xpath-based, and people in Brazil have already done some work on this - 
an archetype-path formalism based on Xpath (this will appear soon at 
this wiki page - 
http://www.openehr.org/wiki/display/spec/A-path+-+Archetype+Path+Language).


> The official standards organisations can set criteria and methods for 
> the how to. However we need a repository and knowledge manager 
> approach to actually handle the examples. Until now only archetypes 
> are stored such a way, HL7 v3 template / XML artefacts would need 
> similar things, e.g. to be included in a CDA or message.

I believe it makes much more sense to just generate them from the 
openEHR archetypes and templates. Messages should just be treated as 
output formats, not clinical model design formalisms (there is no 
re-use, as the world has found out over the last few years).

> My big concern is that an Apgar in archetype is different from an 
> Apgar in CDA or message, DCM helps to bridge the (potential) gap on 
> clinical content and DCM helps to fully specify the concept, the 
> Snomed CT id and the Snomed CT fully specified name or display text 
> (which is currently not possible in an archetype, at least the editor 
> often crashes while doing that).

it will only be different if it is manually modelled to be that way. But 
if we start using a common formalism to do the modelling and generate 
message-related formats, just as we already generate other technical 
forms, then this problem will go away.

- thomas beale