Development and prospective validation of a scoring system for the Basic Endoscopic Skills Training (BEST) box

Aims The increased use of endoscopy as a minimally invasive therapeutic technique has created a great demand for endoscopic training. The Basic Endoscopic Skills Training (BEST) box provides a low-cost solution by adapting the Fundamentals of Laparoscopic Surgery (FLS) box for flexible endoscopic simulation. The BEST box consists of six endoscopic tasks with a 5-min time limit per task. This study aims to develop a scoring system for objective evaluation of user performance. Methods A total of 165 participants were tested on the BEST box. Participants were divided into two groups: retrospective analysis ( n = 100) and prospective analysis ( n = 65). From the retrospective group, 55 individuals were also scored on the Global Assessment of Gastrointestinal Endoscopic Skills-Upper Endoscopy (GAGES-UE). Linear regression between user performance on BEST box and GAGES-UE was performed to develop the scoring system. Receiver Operating Characteristic curve was used to determine a threshold score to help users appreciate their endoscopic expertise. Prospective scoring of 65 individuals was then performed using the formula developed (20 experts and 45 trainees). Results The minimum and maximum possible scores are 30 and 110, respectively. Retrospective analysis showed that the scoring system was able to distinguish between experts and trainees ( p < 0.001), correlated with GAGES-UE ( p < 0.001), and had a reliability constant of r = 0.765 ( p < 0.001). On prospective testing using the scoring system the expert group received a final average score of 92, whereas the average score for the trainee group was 61 ( p < 0.001). Conclusions The developed BEST box scoring system correlates with the experience level of the test taker as well as with the GAGES-UE scoring system. The results of this study add further evidence to the validity of the BEST box as an effective, low-cost endoscopic simulator with the scores used by trainees to track their performance level overtime.