Needle Gauge and Grey Zone Analysis in Endobronchial Ultrasound-Transbronchial Needle Aspiration: The Need for More Randomised Evidence

^aDepartment of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, The Netherlands;

^bDepartment of Pulmonary and Critical Care Medicine, Baylor College of Medicine and Michael E. DeBakey VA Medical Center, Houston, Tex., USA;

^cThoracic Endoscopy and Pulmonology Unit, Ospedali Maggiore e Bellaria, Bologna, Italy