Stream: Orders and Observation WG
Topic: GF#16517
Eric Haas (Jun 04 2018 at 21:20):
Follow up on GF#16517
@Mark Kramer My initial response was/is
1) .focus comments provide clear guidance on where to represent bodysite and specimens. They are common elements for many lab measurements and the suggestion to merge these into .focus would be a major breaking change.
2) "I believe Observation.subject is supposed to capture the latter -- the subject of information." this is incorrect. The .subject is the person of record. The intent of the .focus would be for the the subject of information if different. I felt the examples made this clear. perhaps additiional doco and example is needed.
But from a pure modeling perspective it would be cleaner to roll specimen and bodysite into .focus instead calling them out separately. But I think its probably too late to do that. Welcome suggestions for improved doco...
Mark Kramer (Jun 06 2018 at 17:50):
Hi @Eric Haas , I absolutely agree that BodySite and Specimen must remain separate. I find it quite strange, however, that the Observation.subject is the person of record (aka the patient), for two reasons (1) the word "subject" usually refers to the target of the investigation, and (2) because the subject can be Reference(Patient | Group | Device | Location).
Suppose the observation involves a location associated with the patient, and the observation is 285117005 | Noisy environment (environment) I think the tendency of users would be to put the location in the subject since you are making the observation about the location. But if they do this, there is no association with a patient -- there is nothing in Location that allows association with patient.
Perhaps we should document that the subject is ALWAYS THE PATIENT whose record contains the observation, if there is a PATIENT at all, regardless of whether the observation actually observes the patient? That's a pretty bizarre definition of "subject". I'd call that "patient". A much more straightforward way approach would be to have Observation.patient[OfRecord], and Observation.focus. Then if there is an observation about the patient's home, both would be filled in. If there is an observation about a hospital ward, then only the latter. But Observation.patient would always be a PATIENT. Less confusing, at least to me.
Lloyd McKenzie (Jun 06 2018 at 18:30):
It would be good to make clear that Observation.subject indicates the record the Observation is associated with and is also the default focus of the Observation if no other focus is declared.
Last updated: Apr 12 2022 at 19:14 UTC
