1 George Washington University School of Medicine, Washington, DC, USA.
2 Department of Biostatistics and the Center for Biostatistics in AIDS Research, Harvard T H Chan School of Public Health, Boston, MA, USA.
3 Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA.