1. American College of Physicians, Philadelphia, Pennsylvania (A.Q., T.S., C.H.S.)
2. Portland Veterans Affairs Medical Center and Oregon Health & Science University, Portland, Oregon (A.J.O.)
3. Centers for Disease Control and Prevention, Atlanta, Georgia (L.A.H.)
4. David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California (C.J.C.).