The laparoscopic performance of novice surgical trainees: testing for acquisition, loss, and reacquisition of psychomotor skills.

BACKGROUND: It has been suggested that virtual reality (VR) might be useful for the selection of surgical trainees and the measurement of technical performance during preoperative training and retraining. This study was designed to determine whether it is possible to define and measure the acquisition, loss, and reacquisition of psychomotor skills in novice surgical trainees.
METHODS: Novice surgical trainees (NSTs n = 10, junior surgical registrars with little or no prior experience with laparoscopic surgery) were tested and retested after 1 month using the Minimally Invasive Surgical Trainer-Virtual Reality. Two tasks were used: the simple task [stretch diathermy (SD)] and the more complex task [manipulation diathermy (MD)]. The score was derived from the time taken to complete the task and the number of errors that occurred. Acquisition is the difference between the first and last score of the first training session, loss is the difference in score that occurs between the last score of the first training session and the first score of the second training session, and reacquisition is the difference in the first and last scores of the second training session. A performance criterion level was defined for each task by testing a group of experienced laparoscopic surgeons (n = 10). Groups were compared using the nonparametric Wilcoxon signed rank test, with p < 0.05 considered to be significant.
RESULTS: Acquisition of skill was found for five of 10 NSTs with the SD task and 10/10 for the MD task. As a group the NSTs achieved the criterion level from the outset with the SD task and exceeded it by the eighth attempt for the MD task. The best score was achieved with fewer attempts during the second training session for the SD but not the MD task. The defined parameters are expressed as mean percentage score +/- SD for the 10 NSTs and for each task. There was a 36% (+/- 26) acquisition for the SD task compared with 50% (+/- 4) for the MD task (Wilcoxon p = 0.241). There was a 23% (+/- 19) loss for the SD task compared with 81% (+/- 16) for the MD task (p < 0.005). There was a 20% (+/- 10) reacquisition for the SD task compared with 54% (+/- 7) for the MD task (p < 0.005). The mean scores were greater for the more complex task (MD), which was more useful in discriminating between the individual trainees and the two training sessions.
CONCLUSIONS: It is possible to use VR to define the acquisition, loss, and reacquisition of psychomotor skills in individual NSTs and to compare them with a predefined performance criterion level. This study defines parameters that will be useful in repeated training sessions of NSTs in the preoperative phase of training and during retraining.