Endoscopic injection of urethral bulking agents is an office procedure that is used to treat stress urinary incontinence secondary to internal sphincteric deficiency. Validation studies are important part of simulator evaluation and are considered important step to establish the effectiveness of simulation-based training. The endoscopic needle injection (ENI) simulator has not been formally validated, although it has been used widely at University of California, Irvine. We aimed to demonstrate the descriptive analysis as a first step for the face, content, and construct validities of this simulator in the future.

Dissected female porcine bladders were mounted in a modified Hysteroscopy Diagnostic Trainer (Figure 1).  Using routine endoscopic equipment for this procedure with video monitoring, 6 urologists (experts group) and 6 urology trainee (novice group) completed urethral bulking agent (UBA) injections on a total of 12 bladders using ENI simulator. Face and content validities were assessed by using structured quantitative survey which rating the realism.  Construct validity was assessed by comparing the performance of experts and novices the difference using Objective Structured Assessment of Technical Skills (OSATS). Trainees also completed a post-procedure feedback survey. Effective injections were evaluated by measuring the retrograde urethral opening pressure, visual cystoscopic coaptation, and post-procedure gross anatomic examination.

All 12 participants felt the simulator was a good training tool and should be used as essential part of urology training (face validity).  ENI simulator showed good face and content validity with average score varies between the experts and the novices was 3.9/5 and 3.8/5 respectively. Content validity evaluation showed that most aspects of the simulator were adequately realist (mean Likert scores 3.9-3.8/5). However, the bladder does not bleed, and sometimes thin.

Experts significantly outperformed novices (P<001) across all measure of performance therefore establishing construct validity.

The ENI simulator shows face, content and construct validities, although few aspects of simulator were not very realist ( e.g., bleeding).This study provides a base for the future formal validation for this simulator and for continuing use of this simulator in endourology training.