On Thu, Feb 21, 2008 at 11:18 AM, Oxford Partnership <oxfordpartnership at googlemail.com> wrote: > I have been looking at the OpenEHR Information Model ( ehr_im.pdf ) to get > a better understanding of the underlying classes used within the OpenEHR. > Whilst I am beginning to understand the main classes used within the > archetypes, I am still confused as how they make it to the XML version of > the archetypes. > > For example if you consider the "Composition" class, it has a number of > attributes 'language', 'territory' and 'category' all of which are looking > to be mandatory. > > Now if I look at one composition archetype , ie. > openEHR-EHR-COMPOSITION.prescription.v1.xml > > These attributes are not all present in the XML, why is this?. How can I > know what will be present in the XML form of the archetype?
It's good that you are studying the EHR IM, many common confusions can arise from starting with the AM or an archetype editor only. Your current problem might be caused by one of the most common counfusions regarding openEHR that we meet when introducing students and others to the two level model of openEHR, tell me if this helps: When an archetype is "silent" about something (e.g. an attribute) then the RM (e.g. the attributes of the Composition class) are unrestricted/untouched by the archetype and can be populated by anything that the RM itself allows (in this case e.g. any language or territory). The fact that the archetype tools of today don't show what is unrestricted/untouched in the RM probably make things more confusing than neccesary, most tool developers are aware of this so changes might come about sooner or later. Another soundbite: An archetype not based on a reference model is impossible (or at least pointless). Best regards, Erik Sundvall erisu at imt.liu.se http://www.imt.liu.se/~erisu/ Tel: +46-13-227579
