Bruno Cadonna wrote: > Hi all, > > I have a question regarding dates and times in openehr. > > I read the section "Time in the EHR" on page 29 of the document "The > openEHR Reference Model - EHR Information Model". > > As far as I understood it, OBSERVATION.data.origin and > OBSERVATION.data.event[x].time must not necessarily be within the > interval COMPOSITION.context.start_time and > COMPOSITION.context.end_time or after COMPOSITION.context.start_time. > > Is this right? > > An example: > > A blood pressure measured by a patient on 2008-01-01 (YYYY-MM-DD) and > reported to her physician on 2008-01-02 during an encounter, would > have as COMPOSITION.context.start_time the date 2008-01-02 and as > OBSERVATION.data.origin as well as OBSERVATION.data.event[x].time the > date 2008-01-01. > *This is correct. The general reasoning is that the times in the OBSERVATION history are the 'clinically relevant times' - they are the times the samples were taken from the patient. WIth things like BP, 'sampling' and 'reading the result' occur pretty much together in time and are often within the consultation (but this doesn't have to be so, as your example shows), but for tissue and blood samples, swabs etc the sample times could easily be at an earlier time than when the result-generating activity occurred (e.g. you create a urine sample at home and take it to the lab later on), which is during the time of the health service event.
- thomas beale *
