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For each Encounter NCD creates two types of Events, One is PatientEvent which is used to check whether the patient has satisfied the given conditions ( using Filter Query in the PatientEventStream), and other are some ConceptEvents, which are created from the Encounter Obs, to check whether the Concepts related to the Critic have got satisfied ( using Filter Queries in the ConceptEventStreams).
When a PatientEvent satisfies the given condition CEP will create a new Event called AcceptedPatientEvent and send that to the Sequence Query, similarly when a ConceptEvent gets satisfied an appropriate AcceptedConceptEvent will be created and sent to the Sequence Query. Then when the appropriate AcceptedPatientEvent and the AcceptedConceptEvents have occurred the Sequence Query will create an AcceptedCriticEvent. The AcceptedCriticEvent will then be used to send Critic Notifications.
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