[1] UCL, Dept Epidemiol & Publ Hlth, Mortimer St, London WC1E 7HB, England
[2] Univ Loughborough, Natl Ctr Sport & Exercise Med, Sch Sport Exercise & Hlth Sci, Loughborough, Leics, England
[3] Univ Sydney, Sydney Med Sch, Sch Publ Hlth, Charles Perkins Ctr,Prevent Res Collaborat, Sydney, NSW 2006, Australia
[4] Univ Sydney, Fac Hlth Sci, Sydney, NSW 2006, Australia