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terminologyhl7-fhirucumohdsi-omop

Discrepancy between representation of codes for UCUM in FHIR v OMOP


I’m seeing some differences between what I’m getting in FHIR messages from synthea v. codes in OMOP for UCUM vocabulary. Most of these seem to be around punctuation for lack of a better word (things like _, {, }, [, ], /,. etc.). Examples include (concept_id/FHIR/OMOP):

8876, mmHg, mm[Hg]
44777566, {score}, [score]
9117, mL/min/{1.73_m2}, mL/min/1.73.m2

These codes were specifically found in this resource:

https://syntheticmass.mitre.org/v1/fhir/Patient/6f7acde5-db81-4361-82cf-886893a3280c/$everything

I’m using this version of the OMOP vocabulary:

UCUM
Unified Code for Units of Measure (Regenstrief Institute)
http://aurora.regenstrief.org/~ucum/ucum.html#section-Alphabetic-Index
Version 1.8.2
44819107

Solution

  • If you're seeing mmHg as a UCUM code in FHIR synthea data, that's an error. Similarly, "{score}" is correct, while "[score]" is not. Both mL/min/1.73.m2 and ml/min/{1.73_m2} are valid units, though they're not equivalent.

    I would recommend reporting the issues to Synthea.