Background: 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).
Methods: 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.
Results: 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.
Conclusions: The 6-TSM is a valid and reliable learning tool for surgical residents' acquisition of laparoscopic motor skills.