Expressing numeric values
Up to SNOMED CT Technical discussions

Can anyone tell me how to express a numeric value with Snomed? Take a simple example of "body temperature = 37.7 degC".
I have been scouring the user guidance and compositional grammar / expression constraint documents and have learned about refining concepts with attribute-value pairs but I'm not sure this will work for the example above and similar.
I'm not sure where to put the actual value ("37.5")...is this anywhere close:
386725007|body temperature|;(83568003|Has value (qualifier value)|=37.5,767524001|unit of measure|=258710007|Degrees Celsius (qualifier value)|)
Also, is there an online tool that can validate Snomed expressions?
Thanks,
Chris

Hi Chris
Your logic above appears fine to me, however, can I suggest that you send your query to information.standards@nhs.net as our technical team will be able to give a detailed reply and also let you know if there are any tools that might be useful to you.
You may also like to visit our Delen site where you will find plenty of resources and tools that might be useful to you.
https://hscic.kahootz.com/connect.ti/t_c_home/grouphome
Hope this helps.
Kind regards
Jo Oakes
Knowledge & Information Manager
NHS Digital

Thanks Jo,
I've logged my query with them and will update here once I get a response.
In the meantime, I think I may have come closer to an answer through my own research anyway. It seems that "Concepts to describe numeric values have been added as descendants of 260299005 |Number (qualifier value)| (see https://confluence.ihtsdotools.org/pages/viewpage.action?pageId=71172362). I guess that these, paired with an appropriate attribute, are intended to facilitate the refinement of concepts like body temperature. Like so:
386725007 | Body temperature (observable entity) |:246508008 | Temperature (attribute) |=732706002 | 37.5 (qualifier value) |,246514001 | Units (attribute) |=258710007 | Degrees Celsius (qualifier value) |
However, it does seem a bit clunky to have concepts for all imaginable numbers! Even worse though is that some numbers have concepts while some do not. If I were recording a temperature of 37.4 I could use 732705003 | 37.4 (qualifier value) | but there is no concept for, say, 37.6 or 41 or various other random examples.

Hi Chris
Currently, the international concept model does not include any attributes whose range is a numeric value.
Therefore to create a postcoordinated expression as you described, you would need to extend the concept model with new clearly-defined attributes to support the result value. - e.g. xxxx |Has result value| (Domain: 404684003 |Clinical finding|; Range: DECIMAL)
The following references may be useful:
- SNOMED CT Compositional Grammar - http://snomed.org/scg
- SNOMED CT Editorial Guide - http://snomed.org/eg
- SNOMED CT Machine Readable Concept Model - http://snomed.org/mrcm
Kind Regards
Denise