How do you handle post-coordination with SNOMED CT - do you do any? if not why?

Just to close the circle on this, I have just sent a request to This email address is being protected from spambots. You need JavaScript enabled to view it. requesting information about real-life examples of installations using post-coordination.

I'll post any interesting responses here.

Hi Jon,

Agreed, that was my plan, i.e., if we didn't get enough responses and examples here then we can go to SI directly. I'm going to wait a bit more before contacting SI just in case somebody hasn't read this yet.

Thanks,

-Anibal

Hi Anibal,

I think you've taken the right approach by asking the Canadian community about the use of postcoordination in Canada on this forum.

In terms of contacting SNOMED International, you can pose your question to the general address This email address is being protected from spambots. You need JavaScript enabled to view it.. And since your question is about postcoordination it will be directed to the Implementation Support team.

Regards,

Jon

Thanks Jon for your response.

To tell you the truth, I posted this on behalf of my team, who actually take care of building the different lists for our different clients/products. I know that they look for synonyms and other ways to represent the same concepts they need. My example might not have been the best, but I know for a fact that they do check for alternatives before asking for new concepts to be created.

Your comment about using a different Information Model is what I was after actually, but I wanted to know if anybody has actually done it. I mean, I can think of different ways to implement this without having to necessarily use pre-coordinated concepts, but I just want to know if anybody in Canada has implemented anything with with either post-coordination or some form of Compositional Grammar.

Can you please point me to the Implementation Support team at SNOMED International. Is that just the regular support email? Is there some sort of HTC Forum like this one, but open to all SI members?

Thanks again for your response.

Hi Anibal,

Just wanted to point out a couple of things which relate to your query.

First off 10963951000119101 |Laceration of left knee| is a concept in the International edition and therefore available in the Canadian edition. I appreciate that some may make a clinical distinction between cut and laceration, but I just wanted to point out that sometimes the clinical idea you are thinking of already exists in SNOMED CT as a precoordinated concept, but under another term.

Secondly there is another option to poostcordoination here which may be considered. Using your example, you could design your information model with 3 separate, but related fields.

1) DIAGNOSIS or REASON FOR ENCOUNTER - here you could record 312608009 |Laceration - injury| or 283396008 |Incised wound| (which has a synonym of |Cut|)
2) BODY SITE (optional) - here you could record 72696002 |Knee region structure|
3) LATERALITY (optional) - here you could record 7771000 |Left|

By considering these 3 fields together, one could accurately interpret the intended clinical meaning.

Note that if you decide to take this approach, you would probably want to set up your information model with terminology bindings and compliance with the concept model to avoid conflicts.

For example if you chose 10963951000119101 |Laceration of left knee| in the DIAGNOSIS field above, the other two fields are not applicable because they are understood based on the clinical definition of the concept in SNOMED CT.

You might want to send a message to the Implementation Support team at SNOMED International to ask about postcoordiantion. Or inquire about their languages project group where they often discuss postcoordination.

I hope that helps.

Regards,

Jon Zammit

Hi all,

We're working on a project where we notice lots and lots of terms that are not available in SNOMED CT, mostly due to laterality.

For instance, we need a term with "Cut of left knee", but there's no such thing. There's "Cut of knee" and there's "Left", but not both combined.

It's my understanding that with "post coordination" this can be solved, so that we don't have to create another term for just "Cut of left knee", and another one for "Cut of right knee", and possibly another one for "Cut of both knees".

My team is telling me that a lot of these pre-coordination terms are available in the US Edition, but not in the Canadian one. So, they're requesting ISC/CHI to create the new terms. This seems like a waste of effort, in particular because another country did already the work, but mostly because with post-coordination and using SNOMED CT Compositional Grammar we can accomplish the same thing without creating new terms and bloating even more the SNOMED CT list.

Is anybody using this in real life with some EMR, or some other type of system? I'd love to see how you're handling this at the communication layer and also storage (to actually store these values on the application's side).