1. University of Utah, Department of Pathology, Salt Lake City, UT 84132
2. University of Mississippi Medical Center, Department of Pathology, Jackson, MS 39216
3. Helena Laboratories, Beaumont, TX 77707
4. Unilab Corporation, Tarzana, CA 91356
5. Mayo Clinic, Department of Laboratory Medicine and Pathology, Rochester, MN 55905
6. St. Bartholomew’s Hospital, Clinical Biochemistry Department, London EC1A 7BE, United Kingdom
7. Reno Veterans Affairs Medical Center, Department of Pathology and Clinical Laboratory Services, Reno, NV 89520
8. University of Missouri-Columbia School of Medicine, Departments of Child Health and Pathology, Columbia, MO 65212