Molding mastery: Validation of a 3D-Printed simulator for pediatric inguinal hernia repair

PURPOSE: Pediatric inguinal hernia repair (PIHR) is a common procedure performed using either open or laparoscopic techniques. Both approaches require detailed anatomical knowledge and specialized training. To address these training needs, we developed a low-cost, 3D-printed Pediatric Open and Laparoscopic Integrated Simulator for Inguinal Hernia Repair (POLISHeR). This study aimed to validate POLISHeR as a simulation tool for essential PIHR skills. METHODS: Experienced pediatric surgeons and surgical trainees performed simulated PIHR using POLISHeR. Participants evaluated the simulator's face and content validity using a 5-point Likert scale. Two experienced pediatric surgeons assessed video-recorded simulations using procedure (PCL) and error (ECL) checklists. An Entrustable Professional Activity (EPA) scale measured participants' competence. Construct validity was assessed by comparing expert and trainee performance using the Mann-Whitney U test. RESULTS: Twenty-six participants completed simulations (open: n = 11; laparoscopic: n = 15), including 14 expert pediatric surgeons (open: n = 5; laparoscopic: n = 9). In laparoscopic PIHR, trainees made significantly more errors (p < 0.001), completed fewer key steps (p < 0.001), and received lower EPA scores (p < 0.001) than experts. In open PIHR, trainees made more errors (p = 0.03), had lower EPA scores (p = 0.05), and received lower PCL scores (p = 0.410), though not statistically significant. Experts reported strong anatomical realism and accurate step representation. CONCLUSION: POLISHeR demonstrates strong face, content, and construct validity. It effectively differentiates between expert and trainee performance and represents an affordable, practical tool for teaching and evaluating PIHR skills.