1. Department of Medicine, School of Medicine, University of Washington, Seattle
2. Department of Health Services, School of Public Health, University of Washington, Seattle
3. Department of Biostatistics, School of Public Health, University of Washington, Seattle
4. Department of Neurology, School of Medicine, University of Washington, Seattle
5. Department of Anesthesiology, School of Medicine, University of Washington, Seattle
6. Department of Neurology, School of Medicine, University of Washington, Seattle6Department of Epidemiology, School of Public Health, University of Washington, Seattle