[1] Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[2] Univ Porto, Fac Sport, Rsch Cntr Phys Act Hlth & Leisure, P-4100 Oporto, Portugal
[3] Univ Washington, Dept Med, Cardiovasc Hlth Rsch Unit, Seattle, WA USA
[4] Univ Washington, Dept Epidemiol, Seattle, WA 98195 USA
[5] Univ Vermont, Coll Med, Dept Pathol, Burlington, VT 05405 USA
[6] Brigham & Womens Hosp, Div Network Med, Div Cardiovasc Med & Channing, Boston, MA 02115 USA
[7] Harvard Univ, Sch Med, Boston, MA USA
[8] Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA