Construct and criterion validity testing of the Non-Technical Skills for Surgeons (NOTSS) behaviour assessment tool using videos of simulated operations.

Background: Surgeons' non-technical skills are an important part of surgical performance and surgical education. The most widely adopted assessment tool is the Non-Technical Skills for Surgeons (NOTSS) behaviour rating system. Psychometric analysis of this tool to date has focused on inter-rater reliability and feasibility rather than validation.

Methods: NOTSS assessments were collected from two groups of consultant/attending surgeons in the UK and USA, who rated behaviours of the lead surgeon during a video-based simulated crisis scenario after either online or classroom instruction. The process of validation consisted of assessing construct validity, scale reliability and concurrent criterion validity, and undertaking a sensitivity analysis. Central to this was confirmatory factor analysis to evaluate the structure of the NOTSS taxonomy.

Results: Some 255 consultant surgeons participated in the study. The four-category NOTSS model was found to have robust construct validity evidence, and a superior fit compared with alternative models. Logistic regression and sensitivity analysis revealed that, after adjusting for technical skills, for every 1-point increase in NOTSS score of the lead surgeon, the odds of having a higher versus lower patient safety score was 2·29 times. The same pattern of results was obtained for a broad mix of surgical specialties (UK) as well as a single discipline (cardiothoracic, USA).

Conclusion: The NOTSS tool can be applied in research and education settings to measure non-technical skills in a valid and efficient manner.