Validation of a six-task simulation model in minimally invasive surgery

Abstract

The content validity of currently available inanimate simulation models is questionable, because some tasks seem too far from clinical reality. The aim of this study was to validate a simulation model with six tasks commonly used in clinical practice (6-TSM) for the acquisition of psychomotor skills in minimally invasive surgery (MIS). This was a prospective randomized trial comparing the 6-TSM to a previously described three-task training method (3-TTM). All first, second, and third postgraduate year surgical residents were eligible. The 6-TSM included clipping and dividing of a vessel, excision of lesion, appendectomy, mesh repair, suturing perforation, and hand-sewn anastomosis. The outcome measures of 6-TSM included accuracy error, tissue damage, sliding knot, leak, operating time, and dangerous movements. After completion of training, 6-TSM and 3-TTN residents were tested by the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR). Criterion-related and construct validity, responsiveness, test-retest, and interrater reliability were assessed. During six months, 17 residents underwent training with the 6-TSM or the 3-TTM as allocated. The mean duration of training with 6-TSM and 3-TTM was similar (7.8 vs 8.1 h). The criterion-related validity of the 6-TSM was shown by significantly increased skill improvement in the 6-TSM residents, as compared with the 3-TTM residents at MIST-VR. Construct validity the of 6-TSM was shown by the finding that the experts' baseline was superior to the residents' baseline. The responsiveness of the 6-TSM was shown by the significantly increased skill improvement of the 6-TSM residents in sliding knot, leak, and operating time. The test-retest reliability of the 6-TSM was good (> 0.80), except for accuracy error and dangerous movements (Cronbach's intraclass correlation coefficient alpha: 0.57, p < 0.0001; 0.62, p < 0.0001, respectively). The interrater reliability of the 6-TSM was good (>0.80) except for leak (Kendall's concordance coefficient tau_b:0.76, p = 0.06 for hand-sewn anastomosis) and dangerous movements (tau_b:0.72, p = 0.08 for suturing perforation and tau_b:0.68, p = 0.10 for hand-sewn anastomosis). The perresident cost for 6-TSM was 769 dollars. The 6-TSM is a valid and reliable learning tool for surgical residents' acquisition of laparoscopic motor skills.