1. Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
2. Department of Epidemiology, University of Michigan, Ann Arbor, Michigan, USA
3. Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA
4. Department of Environmental and Occupational Health Sciences, and
5. Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
6. Institute of Social and Preventive Medicine, University of Basel, Basel, Switzerland
7. Department of Biostatistics,
8. Department of Epidemiology, and
9. Department of Medicine, University of Washington, Seattle, Washington, USA