Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is very operator dependent and has a long learning curve. Simulation-based training might shorten the learning curve, and an assessment tool with solid validity evidence could ensure basic competency before unsupervised performance.A total of 16 respiratory physicians, without EBUS experience, were randomised to either virtual-reality simulator training or traditional apprenticeship training on patients, and then each physician performed EBUS-TBNA procedures on three patients. Three blinded, independent assessor assessed the video recordings of the procedures using a newly developed EBUS assessment tool (EBUSAT).The internal consistency was high (Cronbach's α=0.95); the generalisability coefficient was good (0.86), and the tool had discriminatory ability ( p<0.001). Procedures performed by simulator-trained novices were rated higher than procedures performed by apprenticeship-trained novices: mean±SD are 24.2±7.9 points and 20.2±9.4 points, respectively; p=0.006. A pass/fail standard of 28.9 points was established using the contrasting groups method, resulting in 16 (67%) and 20 (83%) procedures performed by simulatortrained novices and apprenticeship-trained novices failing the test, respectively; p<0.001.The endobronchial ultrasound assessment tool could be used to provide reliable and valid assessment of competence in EBUS-TBNA, and act as an aid in certification. Virtual-reality simulator training was shown to be more effective than traditional apprenticeship training. @ERSpublications Virtual-reality simulation-based training shortens the learning curve for endobronchial ultrasound (EBUS)