BACKGROUND: Non-technical skills (NTS) are essential for safe and efficient anaesthesia. Assessment instruments with appropriate validity evidence can be used to ensure that anaesthesiologists possess the NTS necessary to deliver high-standard patient care. The aims were to collect validity evidence using a contemporary validity framework for the assessment instrument Anaesthesiologists' Non-Technical Skills in Denmark (ANTSdk) regarding response process and internal structure (including reliability), and to investigate the effect of rater training on these properties.

METHODS: An explorative study was undertaken at the Danish Institute for Medical Simulation, Copenhagen, Denmark. In a 1-day session, using ANTSdk, a convenience sample of 19 anaesthesiologists rated trainee anaesthesiologists' NTS in nine video-recorded simulation scenarios before and after a 3-h training session.

RESULTS: Response process evidence: participants considered ANTSdk useful and feasible for NTS assessment. Internal structure evidence: inter-rater reliability (single measures) largely expressed substantial agreement (ICC ≥ 0.55 and ICC ≥ 0.60 for pre- and post-training ratings respectively). Strong internal consistency of ratings was found (Spearman's correlation coefficient ≥ 0.82). Accuracy of participants' ratings compared with reference ratings (± 1 scale point) was notable (76% and 78% for pre- and post-training ratings, respectively). The results indicate that the elements 'Demonstrating self-awareness', 'Reassessing decisions', 'Assessing competencies', and 'Supporting others' need more attention in future rater training.

CONCLUSION: The validity evidence collected on content, response process, and internal structure, suggests that ANTSdk is easy to use on video-recorded simulation scenarios, indicating that ANTSdk is a feasible instrument for NTS assessment during anaesthesia training.