Uncovering Immersive Competence as a Hidden Bias in VR-Based Clinical Assessment – A Randomized Controlled Study

Virtual reality (VR) is increasingly used for assessment in educational and clinical settings. However, users’ immersive competence (IC) - the ability to navigate and operate VR systems - may introduce bias unrelated to clinical skills or patient functioning, a relationship that remains unexplored.In this randomized controlled trial, 88 medical students received either general IC training, general plus specific IC training, or no structured training before completing a VR-based assessment scenario. Multimodal outcome data were collected, including physiological stress markers (electrodermal activity), cognitive-load ratings (NASA-TLX), procedural efficiency, and self-reported usability barriers.Specific IC training improved performance compared with control (28.3%±10.3% vs. 21.2%±10.8%, p = .010, d = 0.67), partly mediated by procedural efficiency (η ²  = 0.26) and increased cognitive load (η ²  = 0.15). Prior experience with 3D applications was unrelated to performance in the control group (ρ = 0.165, p = .383) but significantly associated with higher performance in the specific training group (ρ = 0.387, p = .034). Participants reported high enjoyment, although interface barriers distracted untrained users.These findings indicate that IC is a causal, modifiable factor in VR-based assessments and should be accounted for to ensure fair and valid evaluations.