1 Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA. Electronic address: rduan@hsph.harvard.edu.
2 Department of Biostatistics, Epidermiology and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
3 Department of Health Sciences, University of Leicester, Leicester, Leicester, UK.
4 Division of General Internal Medicine, University of Pennsylvania, Philadelphia, PA, USA; Leonard Davis Institute of Health Economics, Philadelphia, PA, USA.
5 Statistical Research and Innovation, Global Biometrics and Data Management, Pfizer Inc., New York, NY, USA; Division of Biostatistics, University of Minnesota, Minneapolis, MN, USA.
6 Department of Biostatistics, Brown University, Providence, RI, USA.