Mixed reality and 3D user interface technologies have increased the immersion, presence, and physicality of user interactions. These technologies can also increase the physicality of embodied conversational agents (ECAs) by making the ECAs occupy and interact with the physical space. We propose that increasing the physicality of an ECA can increase the ECA's social presence, that is, the feeling that the ECA is a real person. In this paper, we examine existing research and formalize the idea of ECA physicality. We also explored the relationship between physicality and social presence by conducting two user studies (n = 18 and n = 29). Both user studies took place in a medical team training context and involved virtual human ECAs as fellow team members. The first study's results suggested that increasing physicality increased social presence and elicited more realistic behavior. The second study's results suggested that individual dimensions of physicality affect social presence to different extents.

The PACU nurses in this study did not consistently share critical information with an attending (virtual) physician during a critical incident, and most missed a fatal dosage error. These findings strongly suggest a crucial need for additional structured team training among practicing health care teams, and they demonstrate the utility of using virtual humans to simulate team members.

Background Simulation in medical education provides students with opportunities to practice interviews, examinations, and diagnosis formulation related to complex conditions without risks to patients. Aim To examine differences between individual and team participation on learning outcomes and student perspectives through use of virtual patients (VPs) for teaching cranial nerve (CN) evaluation. Methods Fifty-seven medical students were randomly assigned to complete simulation exercises either as individuals or as members of three-person teams. Students interviewed, examined, and diagnosed VPs with possible CN damage in the Neurological Exam Rehearsal Virtual Environment (NERVE). Knowledge of CN abnormalities was assessed pre- and post-simulation. Student perspectives of system usability were evaluated post-simulation. Results An aptitude-treatment interaction (ATI) effect was detected; at pre-test scores ≤50%, students in teams scored higher (83%) at post-test than did students as individuals (62%, p = 0.02). Post-simulation, students in teams reported greater confidence in their ability to diagnose CN abnormalities than did students as individuals (p = 0.02; mean rating = 4.0/5.0 and 3.4/5.0, respectively). Conclusion The ATI effect allows us to begin defining best practices for the integration of VP simulators into the medical curriculum. We are persuaded to implement future NERVE exercises with small teams of medical students.