1. Division of Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
2. School of Medicine, Universidad Xochicalco, Tijuana, Baja California, Mexico
3. Centre for Population Health, Burnet Institute, Melbourne, Victoria, Australia
4. School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
5. Centre for Urban Health Solutions, St. Michael's Hospital, Toronto, Ontario, Canada