1. David Geffen School of Medicine, University
of California, Los Angeles, Los Angeles, California;
2. Charles R. Drew University of Medicine and
Science College of Medicine, Los Angeles, California
3. Perelman School of Medicine at the
University of Pennsylvania, Philadelphia, Pennsylvania;
4. Department of Biostatistics, Epidemiology
and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania; and
5. Department of Surgery, Harbor-UCLA Medical
Center, Torrance, California