# SNOMED CT RF2 & ref sets - UML and meta-data diagrams

**URL:** https://discourse.openehr.org/t/snomed-ct-rf2-ref-sets-uml-and-meta-data-diagrams/14976
**Category:** Technical (archive)
**Created:** [16 March 2010 16:01 UTC](https://discourse.openehr.org/t/snomed-ct-rf2-ref-sets-uml-and-meta-data-diagrams/14976 "2010-03-16T16:01:51Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![thomas.beale](https://discourse.openehr.org/user_avatar/discourse.openehr.org/thomas.beale/32/35_2.png) [@thomas.beale](https://discourse.openehr.org/u/thomas.beale)
#### Post date: [16 March 2010 16:01 UTC](https://discourse.openehr.org/t/snomed-ct-rf2-ref-sets-uml-and-meta-data-diagrams/14976/1 "2010-03-16T16:01:51Z")

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As part of reviewing SNOMED CT Release Format 2 (RF2) and Reference Sets specifications, I have created some diagrams which are available here: [http://www.openehr.org/wiki/pages/viewpageattachments.action?pageId=10387459](http://www.openehr.org/wiki/pages/viewpageattachments.action?pageId=10387459)

So far I have a class diagram, and semantic net diagrams of the SNOMED meta-data hierarchy. The latter is really a meta-model hierarchy, used to define the model of other parts of Snomed.

I am still refining the original .vsd, but it is available if anyone wants it.

- thomas beale

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### Author: ![mikael](https://discourse.openehr.org/user_avatar/discourse.openehr.org/mikael/32/881_2.png) [@mikael](https://discourse.openehr.org/u/mikael)
#### Post date: [17 March 2010 08:00 UTC](https://discourse.openehr.org/t/snomed-ct-rf2-ref-sets-uml-and-meta-data-diagrams/14976/2 "2010-03-17T08:00:10Z")

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Hi Thomas,

Since January 2010 is the status “Limited” is handled as an inactive value. (See SNOMED CT Technical Reference Guide Appendix B.)

Greetings,

Mikael

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### Author: ![thomas.beale](https://discourse.openehr.org/user_avatar/discourse.openehr.org/thomas.beale/32/35_2.png) [@thomas.beale](https://discourse.openehr.org/u/thomas.beale)
#### Post date: [17 March 2010 18:38 UTC](https://discourse.openehr.org/t/snomed-ct-rf2-ref-sets-uml-and-meta-data-diagrams/14976/3 "2010-03-17T18:38:59Z")

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thanks Mikael, I have fixed this and various other errors, and improved (according to me 😉 the visual appearance. See [http://www.openehr.org/wiki/pages/viewpageattachments.action?pageId=10387459&sortBy=date&highlight=RF2\_meta\_data-ref\_set\_attr.png&](http://www.openehr.org/wiki/pages/viewpageattachments.action?pageId=10387459&sortBy=date&highlight=RF2_meta_data-ref_set_attr.png&)

- thomas beale