We could use this to see their vitals, life/velocity/integrity/mental state, etc. We could also track any SCPs they are affected by, (1200, 008, 009, etc.) It could be gained via the Vendor, and accessible to JR+.
Stat Tracker could be a cool name if added.
At the end of the test, the researcher could press the “Disconnect” button, terminating the connection to the affected CD.
(Concept taken from the ministry of science.)