FHIR Chat · Observation sample type · implementers

Stream: implementers

Topic: Observation sample type

Gaston Fiore (Jun 22 2016 at 21:16):

I have an observation where I want to indicate that the sample type is blood and the code that I'm using does not indicate this. In the absence of this information as part of the code, what's the best way to report sample type? As a reference to a specimen resource? Or there's some better way? Thanks!

Grahame Grieve (Jun 22 2016 at 21:24):

yes, Specimen.type. if all you have is type, then that's a good use for a contained resource.

Gaston Fiore (Jun 22 2016 at 21:57):

Sorry @Grahame Grieve , I only partly understand your answer. In my observation, I was going to include something like:

"specimen": {
    "reference": "Specimen/blood_sample",
    "display": "Blood sample"
  }

I'm not understanding how I could indicate the Specimen.type directly in this case. Thanks a lot.

Grahame Grieve (Jun 23 2016 at 07:34):

you need a contained resource:

Grahame Grieve (Jun 23 2016 at 07:36):

{
  "resourceType" : "Observation",
  "contained" : [
    {
      "resourceType" : "Specimen",
      "id" : "a1",
      "type" : {.. blood ..}
  ],
  "specimen": {
    "reference": "#a1"
  },

Gaston Fiore (Jun 23 2016 at 13:07):

I see, thanks for the pointer Grahame! I'll read the documentation below:
http://hl7-fhir.github.io/references.html

Eric Haas (Jun 23 2016 at 13:47):

In many use cases I would expect to see an identifier element for the specimen as well. If all you want is to say its blood use a code this is really heavy and using a precoord LOINC would be better. The other option and I'm surpised this has not arisen as a tracker is to make .sample a choice of code or reference like is done in MedicationOrder for medication.

Grahame Grieve (Jun 23 2016 at 13:48):

is it that common to not use pre-coordinated loinc code?

Eric Haas (Jun 23 2016 at 13:51):

I've seen it embedded in the order code and not the observation when using local system codes.

Eric Haas (Jun 23 2016 at 13:54):

As far as common usage, I work with standards related projects always using LOINC
so I can't anwer that.

Last updated: Apr 12 2022 at 19:14 UTC