Establishing Validity for a Vaginal Hysterectomy Simulation Model for Surgical Skills Assessment

OBJECTIVE:To use the Messick validity framework for a simulation-based assessment of vaginal hysterectomy skills.METHODS:Video recordings of physicians at different levels of training and experience performing vaginal hysterectomy on a high-fidelity vaginal surgery model were objectively assessed using a modified 10-item Vaginal Surgical Skills Index, a one-item global scale of overall performance, and a pass-fail criterion. Participants included obstetrics and gynecology trainees and faculty from five institutions. Video recordings were independently assessed by expert surgeons blinded to the identities of the study participants.RESULTS:Fifty surgeons (11 faculty, 39 trainees) were assessed. Experience level correlated strongly with both the modified Vaginal Surgical Skills Index and global scale score, with more experienced participants receiving higher scores (Pearson r=0.81, P<.001; Pearson r=0.74, P<.001). Likewise, surgical experience was also moderately correlated with the modified Vaginal Surgical Skills Index and global scale score (Pearson r=0.55, P<.001; Pearson r=0.58, P<.001). The internal consistency of the modified Vaginal Surgical Skills Index was excellent (Cronbach's alpha=0.97). Interrater reliability of the modified Vaginal Surgical Skills Index and global scale score, as measured by the intraclass correlation coefficient, was moderate to good (0.49-0.95; 0.50-0.87). Using the receiver operating characteristic curve and the pass-fail criterion, a modified Vaginal Surgical Skills Index cutoff score of 27 was found to most accurately (area under the curve 0.951, 95% CI 0.917-0.983) differentiate competent from noncompetent surgeons.CONCLUSION:We demonstrated validity evidence for using a high-fidelity vaginal surgery model with the modified Vaginal Surgical Skills Index or global scale score to assess vaginal hysterectomy skills.