In this pilot study, a new method for visualization through imaging and simulation (VIS-Ed) for teaching diagnosis and treatment of cervical spine trauma was formatively evaluated. The aims were to examine if medical students' self-efficacy would change by training using VIS-Ed, and if so these changes were related to how they evaluated the session, and the user interface (UI) of this program. Using a one-group, pre-post course test design 43 Swedish medical students (4th year, 17 males, 26 females) practiced in groups of three participants. Overall the practice and the UI were considered as positive experiences. They judged VIS-Ed as a good interactive scenario-based educational tool. All students' self-efficacy increased significantly by training (p < 0.001). Spearman's rank correlation tests revealed that increased self-efficacy was only associated with: how the session was compared to as expected (p < 0.007). Students' self-efficacy increased significantly by training, but replication studies should determine if this training effect is gender-related.