1. Division of Pulmonology, Department of Internal Medicine, Medical University of Graz, Graz, Austria;
2. Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria;
3. Department of Biostatistics, Epidemiology, and Informatics, and
4. Division of Cardiovascular Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
5. University of Maryland Institute for Health Computing, Bethesda, Maryland; and
6. Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
7. Department of Medicine and Health Services, Policy, and Practice, Brown University, Providence, Rhode Island