1. Department of Family Medicine and Community Health; University of Massachusetts Medical School; Worcester Massachusetts
2. Department of Social and Preventive Medicine; University of Montréal; Montreal Quebec Canada
3. Centre de recherche du Centre Hospitalier de l'Université de Montréal ; Montreal Quebec Canada
4. Department of Exercise Science; Concordia University; Montreal Quebec Canada
5. Institut national de santé publique du Québec ; Montreal Quebec Canada