1. Department of Medicine, University of Nebraska Medical Center , Omaha, Nebraska , USA
2. Center for Biostatistics in AIDS Research, Harvard T. H. Chan School of Public Health , Boston, Massachusetts , USA
3. Department of Epidemiology, Harvard T. H. Chan School of Public Health , Boston, Massachusetts , USA
4. Department of Medicine, University of Texas Health Science Center at Houston , Houston, Texas , USA
5. Department of Medicine, The Ohio State University School of Medicine , Columbus, Ohio , USA
6. MetroHealth , Cleveland, Ohio , USA
7. Department of Medicine, University of Colorado Denver , Aurora, Colorado , USA