Stream: implementers
Topic: Using modifierExtension to negate contents/code
Bin Mao (Apr 14 2021 at 20:52):
We are trying to convert clinical notes into standard FHIR resources such as Condition or Observation in json format. Is there a proper way to store a negated result?
For example, SNOMED code 716184000 would represent “No known latex allergy”. But not all conditions would have a code to represent the negated meaning. Is there a standard way to represent something like “no nasal congestion” or “no dizziness on standing up” in FHIR resource?
Bin Mao (Apr 16 2021 at 13:33):
We were thinking about using modifierExtension for negation, with just a proper url and “valueBoolean”:false. Is this going to cause any confusion?
Lloyd McKenzie (Apr 16 2021 at 16:22):
It won't cause confusion, but it will limit the set of systems that will be able to consume your instances. Anything that doesn't recognize your extension won't be able to safely use them. It may be better to define separate codes to represent what you want than using standard codes and a modifier extension.
Daniel Venton (Apr 16 2021 at 17:38):
Why wouldn't your dizziness observation use https://loinc.org/45699-6/ for example, which has the answers defined Yes/No.
Bin Mao (Apr 19 2021 at 14:59):
Thanks for the feed back. It's the multiple situations that we are running into that do not have a code to represent negated meaning.
BTW, we used the cTAKES to generate the SNOMED or loinc code, with polarity -1.
Last updated: Apr 12 2022 at 19:14 UTC
