[1] Univ Cambridge, Dept Publ Hlth & Primary Care, Cardiovasc Epidemiol Unit, Cambridge, England
[2] Univ Sussex, SHORE C, Brighton BN1 9RX, E Sussex, England
[3] Inst Publ Hlth, Med Res Council Biostat Unit, Cambridge, England
[4] UCL, EGA Inst Womens Hlth, London, England
[5] Univ Manchester, Fac Med & Human Sci, Manchester, Lancs, England