1. Department of Epidemiology, Columbia University Mailman School of Public Health, New York, New York
2. Department of Medicine, Columbia University Medical Center, New York, New York
3. Department of Medicine and
4. Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, Pennsylvania
5. Department of Radiology, University of Iowa Carver College of Medicine, Iowa City, Iowa
6. Department of Pathology, University of Vermont, Burlington, Vermont
7. Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Connecticut; and
8. Department of Biostatistics, University of Washington, Seattle, Washington