Validation of a virtual reality laparoscopic appendicectomy simulator: a novel process using cognitive task analysis.

BACKGROUND

Virtual reality (VR) simulation is a vital component of surgical training with demonstrated improvements in surgical quality and clinical outcome.

AIMS

To validate the LAP Mentor (Simbionix™) laparoscopic appendicectomy (LA) VR simulator with inclusion of a novel tool, Cognitive Task Analysis (CTA).

METHODS

Thirty-two novices and nine experienced surgeons performed two simulated LAs. An expert-consensus questionnaire guided face validity assessment. Content validity was assessed using CTA-derived questions encompassing eight operative steps and four decision points. Construct validity was evaluated using dexterity metrics, masked assessment of surgical quality using the OSATS global rating scale, and mental workload from two validated tools: the NASA-TLX and SMEQ. Ten novices performed eight further LAs for learning curve assessment.

RESULTS

Face validity was demonstrated across all domains. Considering content validity, the essential technical and non-technical steps were evident. The experienced group performed the procedure quicker (median time 361 vs. 538 s, P = 0.0039) with fewer total movements (426 vs. 641, P < 0.0001) and shorter idle time (131 vs. 199 s, P = 0.0006). This correlated with higher OSATS scores (median 33.5 vs. 22.2, P < 0.0001) and lower mental demand (NASA-TLX: 9.0 vs. 13.75, P = 0.012; SMEQ: 60 vs. 80, P = 0.0025), indicating construct validity. Learning curve data showed statistically significant improvements after the 7th session for procedure time, total movements and idle time, which correlated with reduction in mental demand.

CONCLUSIONS

The LAP Mentor demonstrates face, content and construct validity for LA; thus, it can be used as an effective tool in surgical training. Task repetition leads to achievement of expert benchmarks.