Journal of Surgical Simulation 2019; 6: 11 - 22

Published: 12 April 2019


Original article

Face and construct validation study of novel 3D peg transfer models for training and evaluation of laparoscopic skills in two-dimensional and three-dimensional laparoscopic surgery

Alpa Morawala, Badriya Alaraimi, Gilberto Lazaro Galloso and Bijendra Patel
Corresponding author: Alpa Morawala, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK. Email:


Background: Fundamentals in Laparoscopic Surgery (FLS) is widely used in practice for skill acquisition and objective assessments. The peg transfer model enables trainees to acquire basic laparoscopic skills. We structured three different three-dimensional (3D) peg transfer models with various heights and depths to replicate 3D laparoscopic anatomy. Before implementing any simulation model in a laparoscopy curriculum, it is important to determine its validity.

Aim: To establish face and construct validity of novel 3D peg transfer models in two-dimensional (2D) and 3D visual systems for training and evaluation of laparoscopic skills in novices using the McGill inanimate system.

Methods: Three peg transfer 3D models were designed with different peg heights and depths using wooden blocks from the popular game “Jenga”. Ten novices, ten intermediates and ten experts were recruited. They performed three repetitions of peg transfer on each model using 3D and 2D visual modalities. Performance time, error and total score were measured. Multiple comparison (post hoc Bonferroni) tests were used to compare the data (mean value of total time, total errors and total score) for each group. All participants completed a six-question post-test questionnaire (face validity) for 2D and 3D viewing modalities.

Results: When novices were compared with intermediates and experts using 2D and 3D visual systems, there were statistically significant differences (P < 0.001) in the total score and performance time for all models with the exception of model 2 in 2D. We were unable to show any significant difference in total score and performance
time when intermediates were compared with experts with any of the three models, in either the 2D or the 3D visual modality. All models were highly rated in both visual modalities.

Conclusion: Three models were developed for improving laparoscopic surgical skills. Face validity and construct validity were demonstrated by measuring significant differences in improvement of performance time and lower total score when novices were compared with intermediates and experts in both 2D and 3D visual modalities. We recommend using models 1 and 3 for simulation training in both visual modalities, and this could replace the current relatively “flat” 2D models of the FLS training course to shorten the learning curve for acquiring surgical skills.


FLS; three-dimensional models; two-dimensional models; peg transfer; novices; surgical skills