Background: Unlike other medical specialties, surgery is primarily learned through apprenticeship, by observing surgeons in action during operations. However, the increasing number of medical students and work-hour restrictions limit opportunities for learning in the operating room (OR). These circumstances call for novel technologies, such as immersive video. The objective of this study is to compare knowledge retention, preparedness, and content engagement for surgical learning when watching a surgical video in 3D through a Head-Mounted Display (HMD) versus in 2D video on a conventional screen. Materiel and Methods: This randomized controlled trial includes 231 fourth-year medical students. Participants watched the same 12 min surgical video, narrated by an expert, presented either in immersive 3D form through an HMD, or in 2D form through a conventional screen. The students completed three questionnaires (previewing, postviewing, and 1 month later), which included questions on knowledge retention, expected preparedness, content engagement, tool engagement, and self-assessment. Statistical analyses were adjusted by including the confounding factors. Results: Immediately after the video, the 3D immersive video group showed a significantly lower knowledge retention score compared to the classic video group (P<0.01). Nonetheless, the 3D immersive video group demonstrated better-expected preparedness as a future resident (P=0.019), greater satisfaction (P=0.033), better stimulation (P<0.001), higher involvement (P<0.001), and a greater perceived ability to identify anatomical structures (P<0.001). After 1 month, participants in the immersive video group reported feeling more prepared (P=0.016), more self-confident (P=0.020), more at ease (P=0.023), and less overwhelmed (P<0.01) than those in the 2D video group. Conclusion: Our results showed that 3D surgical immersive video vs. 2D surgical video, enhances the sense of stimulation, satisfaction, involvement, and the perception of having better identified anatomical structures. For early medical school students where access to the OR is limited, this tool appears to a significant step forward in surgical pedagogy. However, the precise understanding of its pedagogical value required further investigation and refinement.

Background/Objectives : Our aim was to evaluate the performance of the reticulocyte hemoglobin content (CHr) assay to diagnose iron deficiency anemia in a context of inflammation in an elderly population, by comparison with the gold standard. Methods: Patients over 18 years old, with anemia and biological inflammatory syndrome, were included consecutively. The accuracy of CHr was compared with that of the gold standard, soluble transferrin receptor/log ferritin. Analyses were performed according to age (subjects over and under 75 years of age) and included specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and the area under the ROC curve (AUC). Results: A total of 174 patients were included, with respectively 84 and 89 patients aged under or 75 years and over, the mean age being 72.5 years (SD 16.9). In the older population, the mean age was 84.6 years (SD 5.2), and 40% were female; the mean hemoglobin was 9.6 (SD 1.4) g/dl and mean CRP 89.7 (SD 72.9) mg/L. The optimal threshold value, determined by maximizing the Youden index, was 25.2pg, at which sensitivity and specificity reached 67% and 94%, respectively. The corresponding PPV and NPV were 62% and 95%. The AUC of the ROC curve was 0.81 with 95% CI: [0.65-0.97], suggesting good diagnostic accuracy. Conclusions: In an elderly population with anemia in a context of inflammation, assessing iron deficiency by including CHr is simple, inexpensive, rapid and practical, as it can be measured as a by-product of a routine complete blood count at little incremental cost, and good NPV can exclude a diagnosis of IDA.