1. Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania Perelman School of Medicine , Philadelphia, PA, USA
2. Kaiser Permanente Washington Health Research Institute, Kaiser Permanente Washington , Seattle, WA, USA
3. Departments of Medicine and Epidemiology and Biostatistics, University of California , San Francisco, CA, USA
4. General Internal Medicine Section, Department of Veterans Affairs, University of California , San Francisco, CA, USA
5. Department of Radiology, University of Washington and Fred Hutchinson Cancer Center , Seattle, WA, USA
6. Division of Biostatistics, Department of Public Health Sciences, University of California Davis , Davis, CA, USA
7. The Dartmouth Institute for Health Policy and Clinical Practice and Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth , Lebanon, NH, USA