Stream: implementers
Topic: Metadata about Observations
Romain LECOLE (Apr 13 2018 at 19:31):
I'm currently trying to figure out what would be the suitable FHIR object to store additional information about an Observation.
The way i see it, an Observation can be seen as a record (a code, a timestamp and a value) but what if i need to add some custom information (metadata) regarding a specific Observation type (like weight or size).
I could add these custom properties as extensions, but since theses properties are metadata that would force the server to send bigger Observation objects containing the same information for every Observation of the same type again and again.
Is there a FHIR object specifically designed to hold metadata like ObservationMetadata or ObservationDefinition?
I thought about :
- StructureDefinition and ElementDefinition but i don't think it can be extended
- CodeSystem and ValueSet, i'm not sure it could be use to fulfill that need
- Use Observation.related not to group but to define to a Observation object holding metadata only (no value).
What would you advice?
Thanks!
Lloyd McKenzie (Apr 13 2018 at 19:47):
You can see a draft here: http://build.fhir.org/observationdefinition.html
Lloyd McKenzie (Apr 13 2018 at 19:47):
Feedback welcome :)
Eric Haas (Apr 14 2018 at 00:10):
'but what if i need to add some custom information (metadata) regarding a specific Observation type (like weight or size).'
I don't understand, can you give a concrete example. Obs def defines the attrbutes of a specific type of observation. ( e.g. when is performed, how much is costs, description, references etc) If you need more context for a specific instance use Obs.components
Romain LECOLE (Apr 16 2018 at 02:00):
That's great thank you very much, i wasn't aware ObservationDefinition was actually a Draft under consideration.
It's pretty much what i was looking for but...
What would you recommend if i wanted to specialize ObservationDefinition per Patient?
ObservationDefinition contains values that could potentially vary from one Patient to another.
Maybe a reference property targeting a Patient could be added on ObservationDefinition object in order to link Patient and ObservationDefinition (just like Observation and Patient already are with the "subject" property)?
But perhaps it wouldn't be the way this resource has been originally intended to be used?
Thank you for your answer.
Romain LECOLE (Apr 16 2018 at 02:11):
With Obs def, do you mean http://build.fhir.org/observationdefinition.html?
If you do, yes that's pretty much what i was looking for (quantitativeDetails and qualifiedInterval for instance).
Eric Haas (Apr 16 2018 at 02:24):
re:
"What would you recommend if i wanted to specialize ObservationDefinition per Patient?
ObservationDefinition contains values that could potentially vary from one Patient to another."
I would think that would live on Observation since that would be an instance and not a type of observation.
Lloyd McKenzie (Apr 16 2018 at 02:41):
Any patient-specific metadata would be time-specific. The parameters relevant for an infant vs. ten-year-old vs. 40-year-old vs. 80-year-old would all be different. If you wanted to capture something broader than each individual Observation, i'd recommend CarePlan.
Romain LECOLE (Apr 17 2018 at 11:45):
Thank you both for your answers!
Last updated: Apr 12 2022 at 19:14 UTC
