The Consistent Time (CT) Integration Profile is part if the IHE IT Infrastructure technical framework.

This profile defines mechanisms to synchronize the time base between multiple actors and computers. Various infrastructure, security, and acquisition profiles require use of a consistent time base on multiple computers. This profile provides median synchronization error of less than 1 second. Configuration options can provide better synchronization. This profile specifies the use of the Network Time Protocol (NTP) defined in RFC 1305.

This profile was previously a portion of the Radiology Basic Security Profile, but it has a variety of other infrastructure uses.

Source: IHE IT Infrastructure Technical Framework rev 5.1