1. 1Department of Laboratory Medicine, National Institutes of Health, Bethesda, MD
2. 2Department of Chemistry, University of Iowa, Iowa City, IA
3. 3Department of Medicine, American Heart Association Comprehensive Hypertension Center, Section of Endocrinology, Diabetes and Metabolism, University of Chicago Medicine, Chicago, IL
4. 4Department of Pathology, University of Virginia Medical School, Charlottesville, VA
5. 5New South Wales Health Pathology Department of Chemical Pathology, Prince of Wales Hospital, Sydney, New South Wales, Australia
6. 6Department of Clinical Sciences, Lund University/CRC, Skane University Hospital Malmö, Malmö, Sweden
7. 7Division of Endocrinology, Northwestern University, The Feinberg School of Medicine, Chicago, IL
8. 8Massachusetts General Hospital Diabetes Center and Harvard Medical School, Boston, MA
9. 9Department of Medicine, University of North Carolina, Chapel Hill, NC