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Aggregated resources are modified versions of upstream resources (e.g. FHIR resources provide directly to a Customer box).
As such, the lastUpdated timestamp of the aggregated resource might be more recent than that of the upstream resource, and hence less meaningful for some use cases.
This extension is generated by PKB to capture help with that problem, and it tracks in priority order:
the value of the upstream http://fhir.patientsknowbest.com/structuredefinition/recorded-date extension (if available)
or else: the meta.lastUpdated value of the upstream resource
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context
This extension is used by many resourcesonly populated on the Appointment resource.
type
Extension
element type
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