A Multicomponent Simulation-Based Program Incorporating Ultrasound for Lumbar Puncture Training in Medical Students: A Randomized Controlled Educational Trial

Background: Lumbar puncture (LP) education requires integration of anatomical knowledge, procedural skills, and safety-related decision-making. Simulation incorporating preprocedural ultrasound localization provides a structured approach to LP training; however, randomized evidence among undergraduate medical students remains limited. Methods: This single-center, parallel-group randomized controlled educational trial included 78 clinical-year medical students randomized to a multicomponent ultrasound-integrated simulation-based LP program (UIS-LP; n = 38) or self-directed learning (SDL; n = 40). The prespecified primary outcome was immediate post-intervention simulation-based LP procedural performance assessed using a 14-item Objective Structured Clinical Examination (OSCE; score range, 0–28). Secondary outcomes included procedural knowledge, ultrasound sonoanatomy identification, self-confidence, simulated vasovagal reaction management, and LP procedural performance at 2–4 weeks. Because of the observed baseline difference in procedural knowledge, the post-intervention procedural-knowledge comparison was evaluated using post hoc ANCOVA adjusted for baseline procedural knowledge. A separate post hoc ANCOVA adjusting for baseline procedural knowledge was conducted as a sensitivity analysis for the primary OSCE outcome. Secondary analyses were exploratory, with a post hoc Bonferroni sensitivity threshold of α = 0.0125. Results: Immediate OSCE scores were 24.42 ± 2.13 in the UIS-LP group and 17.29 ± 4.64 in the SDL group, with a prespecified unadjusted between-group mean difference (UIS-LP − SDL) of 7.13 points (95% CI, 5.49–8.77; Cohen’s d = 1.96; p < 0.001). The post hoc ANCOVA sensitivity analysis yielded an adjusted mean difference of 8.29 points (95% CI, 6.32–10.27; p < 0.001). For procedural knowledge, the baseline-adjusted means were 7.90 for UIS-LP and 4.73 for SDL (adjusted mean difference, 3.17 points; 95% CI, 2.46–3.89; p < 0.001). Mean between-group differences were 2.97 points for ultrasound sonoanatomy identification (95% CI, 2.30–3.64), 9.89 points for self-confidence (95% CI, 7.17–12.61), and 4.24 points for simulated vasovagal reaction management (95% CI, 3.38–5.09); all four immediate exploratory secondary comparisons remained below the post hoc Bonferroni threshold. At the 2–4-week reassessment, the between-group OSCE mean difference was 7.51 points (95% CI, 6.17–8.85; Cohen’s d = 2.54; p < 0.001), whereas the group × time interaction was not statistically significant (β = 0.38 points; 95% CI, −1.67 to 2.44; p = 0.714). No educational or simulation-related unintended events meeting the predefined monitoring criteria were documented. Conclusions: Immediate simulation-based LP procedural-performance scores were higher in the UIS-LP group than in the SDL group, with between-group differences also observed across the exploratory secondary outcomes. At the 2–4-week reassessment, OSCE procedural-performance scores were higher in the UIS-LP group; however, the group × time interaction was not statistically significant, and the reassessment should not be interpreted as evidence of differential skill retention. The findings characterize the multicomponent UIS-LP program as delivered relative to SDL and cannot be attributed specifically to ultrasound or any other individual component. Further studies should examine longer-term procedural performance and whether between-group differences observed in simulation are also present during appropriately supervised patient-based LP practice.