Background
Operator skills are essential for thoracic ultrasound (TUS) to ensure diagnostic accuracy and clinical integration of findings. Immersive virtual reality (IVR) has shown potential within medical education but never to assess TUS skills.
This study aimed to develop an IVR test for assessing TUS skills, gathering validity evidence, and establishing a pass/fail score.
 
Methods
An expert panel developed a practical test based on the TUS protocol by the European Respiratory Society (ERS) including a tutorial and two clinical cases (pleural effusion and interstitial syndrome) using an IVR platform [VitaSim, Denmark]. Four anterior, four lateral, and six posterior zones was available for examination and decision of diagnosis at the virtual patient. Each correct examination equalled one point.
Cronbach?s alpha measured the consistency. Independent t-tests compared performances. The contrasting groups? method was used to set a pass/fail score.

Results
Data was collected at the Clinical Skills Zone during the ERS Congress 2022. We included 13 novices (N, experience: 0 TUS), 22 intermediates (I, 1-50 TUS), and 11 experienced (E, >50 TUS). Cronbach?s alpha was 0.86. The total mean point scores in case 1 (C1) were N: 5.0±2.7; I: 7.3±2.4; E: 8.7±1.3 and in case 2 (C2): N: 4.5±1.8; I: 6.7±2.3; E: 8.5±2.1. Significant differences were found between the N and I for C1 (p=0.007) and C2 (p=0.02), I and E for C1 (p= 0.04) and C2 (p=0.019), and N and E for C1 (p<0.001) and C2 (p<0.001). The pass/fail score was seven points in each case.

Conclusion
We established an IVR test that can distinguish between operators with different TUS skills. This enables a standardized, objective, and evidence-based approach to assess TUS skills.