Development and evaluation of a laparoscopic common bile duct exploration simulator and procedural rating scale

Laparoscopic common bile duct exploration (LCBDE) is an effective, single-stage treatment for choledocholithiasis. However, LCBDE requires specific cognitive and technical skills, is infrequently performed by residents, and currently lacks suitable training and assessment modalities outside of the operating room. To address this gap in training, a simulator model for transcystic and transcholedochal LCBDE was developed and evaluated.

A procedure algorithm incorporating essential cognitive and technical steps of LCBDE was developed, along with a physical model to allow performance of a simulated procedure. Modified Objective Structured Assessment of Technical Skills (OSATS) rating scales were developed to assess performance on the model. Construct validity was assessed by comparing the performance of novices (residents and surgeons without LCBDE experience) versus experienced subjects (surgeons with previous LCBDE experience). Concurrent validity was assessed by comparing scores from the LCBDE scales to those from the standard OSATS scale. Internal consistency and interrater reliability were assessed by comparing performance scores assigned by three independent raters.

Sixteen novices and five experienced subjects performed simulated procedures, with novices scoring lower than experienced subjects on both transcystic (20 ± 3 vs. 33 ± 2 [possible score range, 0-45], p < 0.001) and transcholedochal (25 ± 8 vs. 42 ± 3 [possible score range, 0-53], p < 0.001) rating scales. Scores on the rating scales correlated significantly with scores from the standard OSATS scale. Internal consistency and interrater reliability of the LCBDE rating scales were favorable.

The LCBDE simulator is a low-cost yet realistic physical model that allows performance and evaluation of technical skills required for LCBDE. The LCBDE rating scales show evidence of construct validity, concurrent validity, internal consistency, and interrater reliability. Use of the LCBDE model and associated rating scales allows procedure-specific feedback for trainees and could be used to improve current training.