1 Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, 420-757 West Hastings St. - Federal Tower, Vancouver, BC, V6C 1A1, Canada. dave.stieb@hc-sc.gc.ca.
2 School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Canada. dave.stieb@hc-sc.gc.ca.
3 Department of Public and Occupational Health, Amsterdam Public Health Research Institute, VU University Medical Center Amsterdam, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands.
4 Barcelona Institute for Global Health (ISGlobal), 4c/ Rosselló, 132, 5th 2nd, 08036, Barcelona, Spain.