Representing that a patient has no allergies or intolerances


#1

This isn’t a FHIR question per se, as it probably has more to do with how EMRs currently handle this situation today. We want to be able to distinguish between a patient telling us they have no allergies or intolerances versus not knowing whether a patient has any allergies or intolerances. I did see that there is a STU Note about allowing a value of “Unknown”, which would solve this problem, as would being able to have a value of “None”.

What is more typical in EMRs, having a record of “Unknown”, a record of “None”, or both, and is there a way that the FHIR overseers are leaning?


#2

For us (https://fhir.cerner.com/millennium/dstu2/general-clinical/allergy-intolerance/)

  • No Known Allergies (NKA) or No Known Medication Allergies (NKMA) will be conveyed using the SNOMED codes defined in the Argonaut (DSTU2) and US Core (STU3) profiles.
  • By contrast, Not Asked is conveyed via the absence of information (empty query response).