Neuraxial access procedures, such as spinal blocks, are routine but can be challenging in for example, obese, pregnant, and elderly patients. Ultrasound-based techniques offer a promising alternative, yet standardized assessment tools for evaluating competence are lacking. This study aims to develop and gather validity evidence for a simulation-based assessment tool in ultrasound-assisted and ultrasound-guided neuraxial access, and establish a credible pass/fail score.

A prospective study will be conducted at the Simulation Center, Odense University Hospital, Denmark, and at various anaesthesia departments. Using a low-fidelity mannequin and ultrasound probe, participants with varying experience levels (novices, intermediates, and experienced) will complete both ultrasound-assisted and ultrasound-guided spinal block procedures. Messick's framework of validity, which includes five key sources: content, response process, internal structure, relations to other variables, and consequences of testing, will be used to gather validity evidence for the test. Video recordings of performances will be assessed by blinded raters.

This study will provide evidence for a simulation-based assessment tool for ultrasound-based neuraxial access. Validity evidence will be gathered to ensure the tool accurately measures what is intended and to establish a credible pass/fail standard.

The study addresses a gap in neuraxial access training by developing an objective, simulation-based assessment tool for ultrasound-based procedures in spinal anesthesia. This tool will contribute to structured, competency-based training in ultrasound-based neuraxial access.