The notification of modification of service/resource is triggered on the filler application when the information pertaining to an existing service or resource has been changed for an existing appointment. Services and resources are represented by the AIS, AIG, AIL, and AIP segments on an HL7 scheduling interface transaction. This trigger event should only be used for appointments that have not been completed, or for parent appointments whose children have not been completed.
This trigger event should not be used when an existing resource or service has been replaced in relation to an existing appointment. Instead, use two other trigger events: S20 (notification of cancellation of service resource), as well as S18 (notification of addition of service/resource).