The laparoscopic inguinal and diaphragmatic defect (LIDD) model: a validation study of a novel box trainer model

Damir Ljuhar, Samuel Alexander, Sarah Martin, Ramesh Nataraja

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3 Citations (Scopus)


Background: Paediatric laparoscopic procedures are now becoming routine practice. Therefore, there is a need for simulated laparoscopic models to acquire part-procedural competency prior to direct patient contact in a safe learning environment. For this reason, we chose two paediatric conditions; inguinal hernia (IH) and congenital diaphragmatic hernia (CDH), which were combined to create the laparoscopic inguinal and diaphragmatic defect (LIDD) model. Our aim was to assess this novel surgical simulation model by determining its construct and content validity. Methods: A total of 107 participants completed the validation study: volunteer medical students (novices), surgical trainees (intermediate) and consultant surgeons (experts). Basic demographic data were collected. Subjects were shown a pre-recorded video of both exercises. The assessment exercise involved closing both the simulated inguinal or diaphragmatic hernial orifice. The task was assessed using a novel scoring system with a maximum score of 21 for IH model and 15 for the CDH. The content validity was assessed by a 6-point Likert scale of the expert group. Results: 105/107 participants successfully completed the two exercises. Both aspects of the LIDD model revealed a statistical significance between the scores obtained by the three groups of subjects. Experts scored 20.3/21 for the IH and 14.8/15 for the CDH models which significantly higher than medical students (6.3/21 and 5.3/15; p < 0.05 for both) and trainees (11.2/21 and 9.3/15; p < 0.05 for both). Similarly, trainees performed significantly better than medical students in both models (p < 0.05). Therefore, the LIDD model was found to have a good construct validity. It was, however, unable to differentiate between the various levels of trainees in the intermediate group. Content validity from the experts revealed that there was a high score for the potential of both aspects of LIDD (4.8 and 4.8). There was also a high level of functional fidelity for task completion (4.0 and 4.0). Conclusions: We have demonstrated both the construct and content validity of the LIDD model for both laparoscopic IH and CDH repair. It was able to successfully differentiate between the expert, trainees and inexperienced laparoscopic surgeons.

Original languageEnglish
Pages (from-to)4813-4819
Number of pages7
JournalSurgical Endoscopy
Issue number12
Publication statusPublished - Dec 2018


  • Education
  • Laparoscopic congenital diaphragmatic hernia
  • Laparoscopic inguinal hernia
  • Simulation

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