1. Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA
2. Department of Medicicine, University of California, San Francisco, San Francisco, CA
3. Dell Medical School, University of Texas at Austin, TX
4. Department of Health Policy and Management, Gillings School of Public Health, Chapel Hill, NC
5. School of Medicine, University of North Carolina, Chapel Hill, NC
6. Division of General Medicine, Columbia University Medical Center, New York, NY
7. Department of Pediatrics, University of California, San Francisco, San Francisco, CA