1. Knowledge & Evaluation Research Unit, Division of Diabetes, Metabolism & Nutrition, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. .
2. VA Outcomes Group, Department of Veterans Affairs Medical Center, White River Junction, VT, USA
3. Knowledge & Evaluation Research Unit, Division of Diabetes, Metabolism & Nutrition, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
4. Division of Endocrinology, Diabetes, Metabolism & Nutrition, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA