On 03/12/2010 22:21, Tim Cook wrote: > Hi Tom, > > On Fri, 2010-12-03 at 21:48 +0000, Thomas Beale wrote: >> the general idea has always been that data can always be interpreted >> by a receiver using just the archetypes declared in the data. I >> believe this will continue to be a reliable assumption into the >> future. > So this begs the question. Do you think that there is a possibility > that it will NOT continue to be a reliable assumption?
The current design of ADL 1.5 is that template ids will be declared in the data (since they are just like archetype ids) - see http://www.openehr.org/svn/specification/TRUNK/publishing/architecture/am/knowledge_id_system.pdf So it is really about the mechanisms for sharing archetypes and templates. If specific templates are made available for sharing, then they will be used, just like archetypes. If locally produced specialised archetypes are made available for sharing, the same for them; otherwise the receiver system has to revert back to whatever archetypes and templates it can access. Now, assuming a standardised kind of published service (of which CKM can be considered an initial example) is used, then it just depends on producers 'publishing' archetypes and templates. So far in the national programmes we have seen the intention is to create most templates nationally and share them at that level. The key point to remember is that no matter what reduced set of archetypes or templates are available, *the data received are always correct according to the local artefacts *in use at the sender side (barring software or other system errors of course). So the potential limitations at the receiver are to do with: * not having the archetype information for *added data points*, due to not having specialised archetypes produced locally at the origin. o this is correct: if the definition of those added items were of interest outside the producer site, it would have published the relevant archetypes somewhere o regardless, the data structures are always openEHR standard structures, and the receiver can always process them in a generic way. * not having the templates: the only limitation here is not knowing what restrictions (*removed data points, more constrained term sets*) were specified in the template above those of the underlying archetypes. o this is also correct: this would only matter if the receiver wanted to allow users to modify the data according to the same templates as at the senders location; if this is true, it means that the receiver wants to share the templates, and they will have arranged to do this. >> However, with the new style templates, which are essentially just >> archetypes, it may be that templates will be shared quite often as >> well, since the computing machinery that can deal with archetypes will >> be able to deal with ADL 1.5 templates as well (with only very minor >> upgrades from today, since we are talking about operational templates, >> which are essentially big archetypes). > So in a paragraph or less can you explain the difference between > templates and simply constructing archetypes that use slots for > extendability? Archetypes contain slots; templates fill them and remove unwanted archetype data points (generally most of them in any given template). It is a matter for discussion whether templates should ever be allowed to add new data points the way an archetype can. >> This is not going to add much information, since the information >> structures themselves (i.e. the compositional hierarchy of >> Composition, Sections, Entries etc) will reflect the structure of the >> template that was used. But if the receiver wants to validate the >> received data against the template, > But if the data validates against the archetype(s) (and therefore the > reference model) there is no need to validate against templates. at the receiver side, correct. Unless the receiver wants to do that for some reason, e.g. to enable users to further modify the data according to the same rules as at the sender, in which case sharing is required. > > But the point I am making is that templates do not have to be shared in > order to interpret the data. Again, the only information a template can > add is what particular subsets were available at the time a specific > entry was chosen. I simply do not see a purpose for this 'requirement'. > The data has been entered. It is now part of a historical record. > Since the archetype describes the data model of the concept as a set of > constraints against the reference model. That is all the validation > required. > > Again, if I am missing something I am very interested in what it is. > > Thanks, > Tim for interpreting data, I would agree. For doing other things, possibly not. - thomas * * -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/mailman/private/openehr-technical_lists.openehr.org/attachments/20101205/cf9fb5cd/attachment.html>
