1. Departments of Psychiatry, Neurology, Epidemiology and Biostatistics, University of California, San Francisco, CA and San Francisco VA Medical Center, San Francisco, CA
2. Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA
3. Northern California Institute for Research and Education, San Francisco, CA
4. Department of Public Health Sciences, University of Chicago, Chicago, IL
5. Department of Medicine, University of Chicago, Chicago, IL
6. Department of Preventive Medicine, Northwestern University, Chicago, IL
7. Intramural Research Program, National Institute on Aging, Bethesda, MD
8. Department of Medicine, University of Alabama, Birmingham, AL
9. Division of Research, Kaiser Permanente Northern California, Oakland, CA