resourceType

Unique identifier given to each specific type of <a target='_blank' href='https://hl7.org/fhir/R4/resourcelist.html'>resource</a> defined in the FHIR specification

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Each FHIR resource type has its own set of attributes, which define the structure and content of <a target='_blank' href='https://hl7.org/fhir/R4/observation.html'>that resource</a>