1. Division of Pulmonary and Critical Care Medicine, Department of Medicine; Brigham and Women's Hospital, Harvard Medical School; Boston Massachusetts USA
2. Division of Pulmonary Diseases & Critical Care; University of Texas Health Science Center; San Antonio Texas USA
3. Division of Pulmonary & Critical Care Medicine; University of Michigan Health System; Ann Arbor Michigan USA
4. Department of Radiology; University of California; San Diego California USA
5. Department of Radiology; Temple University Hospital; Philadelphia Pennsylvania USA
6. Department of Radiology; National Jewish Health; Denver Colorado USA
7. Colorado School of Public Health; University of Colorado Denver; Aurora Colorado USA
8. Department of Radiology; Brigham and Women's Hospital, Harvard Medical School; Boston Massachusetts USA