Efficiency monitor was a position held by Annika Hansen after being brainwashed by the Quarren Doctor Kadan in 2377. In this capacity she enforced labor protocols, including minimizing fraternization between employees during work hours.
Following the introduction of Kathryn Janeway and Jaffen, they were confronted by Hansen, reminding them of the plant's policies. Tom Paris later revealed to Umali that he was fired from his previous position because he "had a disagreement with the new efficiency monitor," because "she didn't think my work was very efficient." (VOY: "Workforce")