AOM 1.4 - Archetype.uid a UUID or OID?

Thomas Beale thomas.beale at
Fri Jun 16 15:12:58 EDT 2017

It's not correct to say that HIER_OBJECT_ID can represent anything. It 
can represent ids that are made of a UID root (either a UUID or OID or 
domain name or reverse domain name) and a String extension. While the 
String part could be abused, it isn't in properly built software. As can 
be seen in the model 
there quite a few other identifier types as well.

You are right about the error you mention however, we need to fix the 
documentation for that.

- thomas

On 16/06/2017 10:05, Bert Verhees wrote:
> I have a few thoughts, although the question has become less urgent to 
> me, because I can use the HIER_OBJECT_ID to store a UUID. Which is a 
> bit funny, but it is correct following the OpenEHR specs, so I can 
> convince others that it is right.
> On 16-06-17 01:36, Heath Frankel wrote:
>> No one uses OIDs and this is not the problem.
> I believe that William Goossen is depending on OID's in DCM, in which 
> archetypes can play a role. But for his case, he can add a 
> description-field, containing a OID. I think that would be better for 
> him, because then he can trust that there is always a usable OID in 
> the archetypes he refers to and not, like now in 99% of the archetypes 
> is the case in the uid-property, a UUID.
>> The issue is AOM 1.4 uses the complex type HIER_OBJECT_ID which has a 
>> value attribute of type UID while AOM 2.0 uses simple type of UUID.
> I think, best is when there is uniformity in the use of the standard, 
> the HIER_OBJECT_ID, which can be anything, with every possible 
> semantic meaning does not look right in a standard. As is in the 
> definition, the uid serves as a machine-readable identifier equivalent 
> to the archetype-id, which is human readable. For this purpose, it 
> needs to be unique.
> But how hard is it for a computer to check if a ID is unique, when the 
> computer must guess what kind of Id is used? I think the definition of 
> the uid needs to be tighter. Now it is said in the specs:  uid: 
> HIER_OBJECT_ID: "OID identifier of this archetype."
> This is definitely wrong, it can be anything, as long as it fits in 
> HIER_OBJECT_ID, which is quite a lot, and my original question was to 
> change the specs.**
> And the best thing is to change it to its common practical use, which 
> is UUID.
> Best regards
> Bert
> _______________________________________________
> openEHR-technical mailing list
> openEHR-technical at

Thomas Beale
Principal, Ars Semantica <>
Consultant, ABD Team, Intermountain Healthcare 
Management Board, Specifications Program Lead, openEHR Foundation 
Chartered IT Professional Fellow, BCS, British Computer Society 
Health IT blog <> | Culture blog 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the openEHR-technical mailing list