1. Michael A. Stoto is with Georgetown University, Washington, DC, and the Harvard T. H. Chan School of Public Health, Boston, MA. Charles Rothwell is retired and was formerly with the National Center for Health Statistics, Hyattsville, MD. Maureen Lichtveld is with the Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA. Matthew K. Wynia is with the University of Colorado School of Medicine and Colorado School of Public Health, Aurora.