1. Blood Systems Research Institute, San Francisco, California, USA;University of California, San Francisco, California, USA;
2. Westat, Rockville, Maryland, USA;
3. Blood Systems Research Institute, San Francisco, California, USA;
4. American Red Cross National Testing and Reference Laboratories, Gaithersburg, Maryland, USA;
5. Blood Systems Research Institute, San Francisco, California, USA;Westat, Rockville, Maryland, USA;University of British Columbia, Victoria, British Columbia, Canada;
6. Focus Diagnostics, Cypress, California, USA;
7. America's Blood Centers, Washington DC, USA;
8. Centers for Disease Control and Prevention, Fort Collins, Colorado, USA;
9. National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA