An action that is or was performed on a patient (e.g., a surgical procedure) or on behalf of a patient (e.g., a laboratory procedure). Note that this class contains a flag that indicates whether the procedure was completed; if it was not completed, the nonCompletionTimeFrame attribtue would contain the time that the procedure was originally scheduled to be completed. CIMI has a separate NonCompletionContext subclass, which the FHIM combines with the PerformanceContext in order to avoid multiple inheritance problems. "An Act whose immediate and primary outcome (post-condition) is the alteration of the physical condition of the subject." - HL7 V3. "An action that is or was performed on or for a patient. This can be a physical intervention like an operation, or less invasive like long term services, counseling, or hypnotherapy." - HL7 FHIR, Procedure