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OpenCodelists is an open platform for creating and sharing codelists of clinical terms and drugs.
https://www.opencodelists.org
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Medicines Definition Builder: Snomed hierachy link to dm+d #177

Open brianmackenna opened 3 years ago

brianmackenna commented 3 years ago

In #176 I have recorded some notes. Although NHS dm+d exists as a standalone comprehensive reference source it actually is the local UK extension of SnoMed. We can utilise the hierarchies of snomed to support categorisation and building codelists. As we know Snomed is quite extensive and complex, some of the categories don't actually make sense to me however using the East Kent browser and the Australian Shrimp browser it looks like it will be very useful.

Using Atorvastatin 20mg chewable tabs and taking the ancestors displayed on EK browser here are some examples and uses of the SnoMed hierarchy.

Snomed CT ancestor Brian’s expectation
Enzyme inhibitor-containing product Unexpected but useful. Enzyme inhibition is not a black and white issue - this classification is more suited to decision support type content as opposed to blac&white ontology.
Nitrogen and nitrogen compound-containing product I had no clue atorvastatin has nitrogen in it and not a clue of relevance clinically. It is accurate! There will be chemists, different flavours of nerd pharmacists and pharmacologists who might make use of searching or studies where the principle chemical components are of interest as opposed to mechanism of action/clinical use.
HMG-CoA reductase inhibitor-containing product Expected - this is technical term for statins, named after mechanism of action.
Azole-containing product Similar to N but in this case I can’t see an azole in the chemical structure. (note to check accuracy when have time but I imagine it is fine)
Atorvastatin Expected
inglesp commented 3 years ago

The termbrowser knows that 19722511000001105 (Atorvastatin 20mg chewable tablets sugar free) is a 108600003 (Product containing atorvastatin) because 108600003 is the dm+d code for the Atorvastatin VTM.

@brianmackenna have you done any work to see whether all dm+d VTMs are in SNOMED?

brianmackenna commented 3 years ago

No

brianmackenna commented 2 years ago

These SNOMED Drug Extension User Support Group has some useful documents and presentations that might be useful for when we get to this.

It would also be good to consider #525 if we do a comprehensive job on this issue.

Jongmassey commented 3 months ago

I guess the difference between using the SNOMED-CT hierarchy in this case and VTMs is that if you want a robust "all statins" codelist algorithm then "HMG-CoA reductase inhibitor-containing product" is the key concept. If you a priori know all the VTMs that are statins then you can you use the VTM table, but what happens when a new statin comes to market?

Jongmassey commented 3 months ago

It also lets you drill up to things like "Antilipemic agent". Questions like "what proportion of prescribing of lipid-lowering drug prescribing is statins?" that are currently most easily answered by comparing prescribing in various bits of the BNF hierarchy can be answered in dm+d by bringing in the snomed hierarchy.