Stereoscopic three-dimensional visualisation technology in anatomy learning: A meta-analysis.

OBJECTIVES: The features that contribute to the apparent effectiveness of three-dimensional visualisation technology [3DVT] in teaching anatomy are largely unknown. The aim of this study was to conduct a systematic review and meta-analysis of the role of stereopsis in learning anatomy with 3DVT. METHODS: The review was conducted and reported according to PRISMA Standards. Literature search of English articles was performed using EMBASE, MEDLINE, CINAHL EBSCOhost, ERIC EBSCOhost, Cochrane CENTRAL, Web of Science and Google Scholar databases until November 2019. Study selection, data extraction and study appraisal were performed independently by two authors. Articles were assessed for methodological quality using the Medical Education Research Study Quality Instrument and the Cochrane Collaboration's tool for assessing the risk of bias. For quantitative analysis, studies were grouped based on relative between-intervention differences in instructional methods and type of control conditions. RESULTS: A total of 3934 citations were obtained of which 67 underwent a full-text review. Ultimately, 13 randomised controlled trials were included in the meta-analysis. When interactive, stereoscopic 3D models were compared to interactive, monoscopic 3D models within a single level of instructional design, for example isolating stereopsis as the only true manipulated element in the experimental design, an effect size [ES] of 0.53 (95% confidence interval [CI] 0.26-0.80; P < .00001) was found. In comparison with 2D images within multiple levels of instructional design, an effect size of 0.45 (95% CI 0.10-0.81; P < .002) was found. Stereopsis had no effect on learning when utilised with non-interactive 3D images (ES = -0.87, 95% CI -2.09-0.35; P = .16). CONCLUSION: Stereopsis is an important distinguishing element of 3DVT that has a significant positive effect on acquisition of anatomical knowledge when utilised within an interactive 3D environment. A distinction between stereoscopic and monoscopic 3DVT is essential to make in anatomical education and research.

Effect of binocular disparity on learning anatomy with stereoscopic augmented reality visualization: A double center randomized controlled trial.

Binocular disparity provides one of the important depth cues within stereoscopic three-dimensional (3D) visualization technology. However, there is limited research on its effect on learning within a 3D augmented reality (AR) environment. This study evaluated the effect of binocular disparity on the acquisition of anatomical knowledge and perceived cognitive load in relation to visual-spatial abilities. In a double-center randomized controlled trial, first-year (bio)medical undergraduates studied lower extremity anatomy in an interactive 3D AR environment either with a stereoscopic 3D view (n = 32) or monoscopic 3D view (n = 34). Visual-spatial abilities were tested with a mental rotation test. Anatomical knowledge was assessed by a validated 30-item written test and 30-item specimen test. Cognitive load was measured by the NASA-TLX questionnaire. Students in the stereoscopic 3D and monoscopic 3D groups performed equally well in terms of percentage correct answers (written test: 47.9 ± 15.8 vs. 49.1 ± 18.3; P = 0.635; specimen test: 43.0 ± 17.9 vs. 46.3 ± 15.1; P = 0.429), and perceived cognitive load scores (6.2 ± 1.0 vs. 6.2 ± 1.3; P = 0.992). Regardless of intervention, visual-spatial abilities were positively associated with the specimen test scores (η2 = 0.13, P = 0.003), perceived representativeness of the anatomy test questions (P = 0.010) and subjective improvement in anatomy knowledge (P < 0.001). In conclusion, binocular disparity does not improve learning anatomy. Motion parallax should be considered as another important depth cue that contributes to depth perception during learning in a stereoscopic 3D AR environment.

Development of a Virtual Three-Dimensional Assessment Scenario for Anatomical Education.

In anatomical education three-dimensional (3D) visualization technology allows for active and stereoscopic exploration of anatomy and can easily be adopted into medical curricula along with traditional 3D teaching methods. However, most often knowledge is still assessed with two-dimensional (2D) paper-and-pencil tests. To address the growing misalignment between learning and assessment, this viewpoint commentary highlights the development of a virtual 3D assessment scenario and perspectives from students and teachers on the use of this assessment tool: a 10-minute session of anatomical knowledge assessment with real-time interaction between assessor and examinee, both wearing a HoloLens and sharing the same stereoscopic 3D augmented reality model. Additionally, recommendations for future directions, including implementation, validation, logistic challenges, and cost-effectiveness, are provided. Continued collaboration between developers, researchers, teachers, and students is critical to advancing these processes.

The effect of a three-dimensional instructional video on performance of a spatially complex procedure in surgical residents in relation to their visual-spatial abilities.

BACKGROUND: The effect of three-dimensional (3D) vs. two-dimensional (2D) video on performance of a spatially complex procedure and perceived cognitive load were examined among residents in relation to their visual-spatial abilities (VSA). METHODS: In a randomized controlled trial, 108 surgical residents performed a 5-Flap Z-plasty on a simulation model after watching the instructional video either in a 3D or 2D mode. Outcomes included perceived cognitive load measured by NASA-TLX questionnaire, task performance assessed using Observational Clinical Human Reliability Analysis and the percentage of achieved safe lengthening of the scar. RESULTS: No significant differences were found between groups. However, when accounted for VSA, safe lengthening was achieved significantly more often in the 3D group and only among individuals with high VSA (OR = 6.67, 95%CI: 1.23-35.9, p = .027). CONCLUSIONS: Overall, 3D instructional videos are as effective as 2D videos. However, they can be effectively used to enhance learning in high VSA residents.

Global versus task-specific postoperative feedback in surgical procedure learning.

BACKGROUND: Task-specific checklists and global rating scales are both recommended assessment tools to provide constructive feedback on surgical performance. This study evaluated the most effective feedback tool by comparing the effects of the Observational Clinical Human Reliability Analysis (OCHRA) and the Objective Structured Assessment of Technical Skills (OSATS) on surgical performance in relation to the visual-spatial ability of the learners. METHODS: In a randomized controlled trial, medical students were allocated to either the OCHRA (n = 25) or OSATS (n = 25) feedback group. Visual-spatial ability was measured by a Mental Rotation Test. Participants performed an open inguinal hernia repair procedure on a simulation model twice. Feedback was provided after the first procedure. Improvement in performance was evaluated blindly using a global rating scale (performance score) and hand-motion analysis (time and path length). RESULTS: Mean improvement in performance score was not significantly different between the OCHRA and OSATS feedback groups (P = .100). However, mean improvement in time (371.0 ± 223.4 vs 274.6 ± 341.6; P = .027) and path length (53.5 ± 42.4 vs 34.7 ± 39.0; P = .046) was significantly greater in the OCHRA feedback group. When stratified by mental rotation test scores, the greater improvement in time (P = .032) and path length (P = .053) was observed only among individuals with low visual-spatial abilities. CONCLUSION: A task-specific (OCHRA) feedback is more effective in improving surgical skills in terms of time and path length in novices compared to a global rating scale (OSATS). The effects of a task-specific feedback are present mostly in individuals with lower visual-spatial abilities.

Anatomy Dissection Course Improves the Initially Lower Levels of Visual-Spatial Abilities of Medical Undergraduates.

Visual-spatial abilities are considered a successful predictor in anatomy learning. Previous research suggest that visual-spatial abilities can be trained, and the magnitude of improvement can be affected by initial levels of spatial skills. This case-control study aimed to evaluate (1) the impact of an extra-curricular anatomy dissection course on visual-spatial abilities of medical undergraduates and (2) the magnitude of improvement in students with initially lower levels of visual-spatial abilities, and (3) whether the choice for the course was related to visual-spatial abilities. Course participants (n = 45) and controls (n = 65) were first and second-year medical undergraduates who performed a Mental Rotations Test (MRT) before and 10 weeks after the course. At baseline, there was no significant difference in MRT scores between course participants and controls. At the end of the course, participants achieved a greater improvement than controls (first-year: ∆6.0 ± 4.1 vs. ∆4.9 ± 3.2; ANCOVA, P = 0.019, Cohen's d = 0.41; second-year: ∆6.5 ± 3.3 vs. ∆6.1 ± 4.0; P = 0.03, Cohen's d = 0.11). Individuals with initially lower scores on the MRT pretest showed the largest improvement (∆8.4 ± 2.3 vs. ∆6.8 ± 2.8; P = 0.011, Cohen's d = 0.61). In summary, (1) an anatomy dissection course improved visual-spatial abilities of medical undergraduates; (2) a substantial improvement was observed in individuals with initially lower scores on the visual-spatial abilities test indicating a different trajectory of improvement; (3) students' preferences for attending extracurricular anatomy dissection course was not driven by visual-spatial abilities.

The Effect of Stereoscopic Augmented Reality Visualization on Learning Anatomy and the Modifying Effect of Visual-Spatial Abilities: A Double-Center Randomized Controlled Trial.

Monoscopically projected three-dimensional (3D) visualization technology may have significant disadvantages for students with lower visual-spatial abilities despite its overall effectiveness in teaching anatomy. Previous research suggests that stereopsis may facilitate a better comprehension of anatomical knowledge. This study evaluated the educational effectiveness of stereoscopic augmented reality (AR) visualization and the modifying effect of visual-spatial abilities on learning. In a double-center randomized controlled trial, first- and second-year (bio)medical undergraduates studied lower limb anatomy with stereoscopic 3D AR model (n = 20), monoscopic 3D desktop model (n = 20), or two-dimensional (2D) anatomical atlas (n = 18). Visual-spatial abilities were tested with Mental Rotation Test (MRT), Paper Folding Test (PFT), and Mechanical Reasoning (MR) Test. Anatomical knowledge was assessed by the validated 30-item paper posttest. The overall posttest scores in the stereoscopic 3D AR group (47.8%) were similar to those in the monoscopic 3D desktop group (38.5%; P = 0.240) and the 2D anatomical atlas group (50.9%; P = 1.00). When stratified by visual-spatial abilities test scores, students with lower MRT scores achieved higher posttest scores in the stereoscopic 3D AR group (49.2%) as compared to the monoscopic 3D desktop group (33.4%; P = 0.015) and similar to the scores in the 2D group (46.4%; P = 0.99). Participants with higher MRT scores performed equally well in all conditions. It is instrumental to consider an aptitude-treatment interaction caused by visual-spatial abilities when designing research into 3D learning. Further research is needed to identify contributing features and the most effective way of introducing this technology into current educational programs.