1. Department of General Internal Medicine, Allegheny General Hospital, Pittsburgh, Pennsylvania, USA.
2. Department of Family Medicine, Mayo Clinic, Rochester, Minnesota, USA.
3. Division of Women's Health Internal Medicine, Mayo Clinic, Scottsdale, Arizona, USA.
4. Mayo Clinic, Jacksonville, Florida, USA.
5. Division of General Internal Medicine, Mayo Clinic, Jacksonville, Florida, USA.
6. Department of Community Internal Medicine, Mayo Clinic, Scottsdale, Arizona, USA.
7. Department of Family Medicine, Mayo Clinic, Scottsdale, Arizona, USA.
8. Department of Radiology, Mayo Clinic, Scottsdale, Arizona, USA.
9. Division of Biostatistics and Bioinformatics, Department of Health Sciences Research, Scottsdale, Arizona, USA.