2018 - Sandeep Nayar

Novel Evaluation of a Laparoscopic Appendicectomy Virtual Reality Simulator using Cognitive Task Analysis

Aim: Validate the LAP Mentor (SimbionixTM) laparoscopic appendicectomy (LA) virtual reality simulator including the novel use of Cognitive Task Analysis (CTA).

Method: Thirty-two novices and nine experts (>100 LAs) performed two simulated LAs. An expert consensus questionnaire guided face validity assessment. 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. Content validity was assessed using CTA-derived questions encompassing eight essential operative steps and four decision points. Ten novices performed eight further LAs for learning curve assessment.

Result: The simulator demonstrated face validity across all domains. The experts performed the procedure quicker (median time 361 vs. 513 seconds, P=0.0039) with fewer movements (P<0.0001). This correlated with higher OSATS scores (median 33.5 vs. 22.4, P<0.0001) and less mental demand in both the NASA-TLX (P=0.012) and SMEQ (P=0.0034), indicating construct validity. Considering content validity, the essential technical and non-technical steps were evident. Learning curve analysis displayed a plateau after the 7th session for time.

Conclusion: 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.