1. Department of Medicine, Case Western Reserve University, Cleveland, Ohio
2. Departments of Medicine and Anesthesiology, University of Pittsburgh, Pittsburgh, Pa
3. Department of Biostatistics, University of Washington, Seattle, Wash
4. Department of Medicine and Respiratory Science Center, University of Arizona, Tucson, Ariz
5. Department of Medicine, University of Minnesota, Minneapolis, Minn
6. Department of Medicine, Boston University, Boston, Mass
7. Department of Medicine, University of California, Davis, Calif
8. Department of Medicine, New York University, New York, NY
9. Department of Medicine, Johns Hopkins University, Baltimore, Md
10. National Heart, Lung, and Blood Institute, NIH, Bethesda Md