1 MedStar Health Research Institute, Hyattsville, MD, USA. 2 Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. 3 Tufts Medical Center, Boston, MA, USA. 4 KGS for The National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA. 5 Kaiser Permanente Center for Health Research NW, Portland, OR, USA. 6 Atlanta VA Medical Center, Decatur, GA, USA. 7 Emory University School of Medicine, Atlanta, GA, USA. 8 Maine Medical Center, Scarborough, ME, USA. 9 HealthPartners, Minneapolis, MN, USA. 10 Duke University School of Medicine, Durham, NC, USA. 11 University of Kansas Medical Center, Kansas City, KS, USA. 12 Georgia Department of Public Health, Atlanta, GA, USA. 13 University of Nebraska Medical Center, Omaha, NE, USA.