Novice learning curves for laparoscopic virtual reality training: implications for competency

Abstract

Current literature suggests that novices reach a plateau after only 2 to 7 trials when training on the MIST VR laparoscopic virtual reality system. We hypothesize that significant benefit may be gained by additional training. As part of a surgical interest group, second-year medical students (n = 12) voluntarily enrolled under an IRB-approved protocol for MIST VR training. Subjects (ages 24–31, 4 women, 8 men) completed pre-training and post-training questionnaires and performed 30 repetitions of all 12 tasks. Performance data were recorded for each trial, including time, errors, economy of motion and diathermy, and overall score. Learning curves for each task were generated by fitting spline curves to the mean overall scores for each repetition. Repeated measurements using mixed models were compared for trials 1–10, 11–20, and 21–30. Plateaus were defined as no statistical difference between clusters of 10 trials. On average, subjects completed training in 7.1 hrs. (range 5.9–9.2). During 30 repetitions, a plateau in performance was detected for all 12 MIST VR tasks. The plateau was reached in the first 10 trials for one task, during the second 10 trials for 4 tasks and during the third 10 trials for 7 of the 12 tasks. All participants noted subjective improvement in their laparoscopic technical skills following training. Laparoscopic self-rating scores improved by 1.6 points according to a 5-point Lickert scale (p < 0.05). These data indicate that a plateau in performance is reached in fewer than 10 trials in only 1 of 12 MIST VR tasks. The majority of tasks require 21–30 trials before a plateau is reached. We conclude that a significant and variable amount of training may be required to achieve maximal benefit. Neither a predetermined training duration nor an arbitrary number of repetitions may be adequate to ensure laparoscopic competency following simulator training.