[1] Kings Coll London, Inst Psychiat Psychol & Neurosci, Hlth Serv & Populat Res Dept, London, England
[2] UCL, UCL Social Res Inst, Ctr Longitudinal Studies, London, England
[3] Kings Coll London, ESRC Ctr Soc & Mental Hlth, London, England
[4] Newcastle Univ, Populat Hlth Sci Inst, Fac Med Sci, Newcastle Upon Tyne, England
[5] Brown Univ, Ctr Gerontol & Healthcare Res, Providence, RI USA
[6] WHO, Maternal Newborn Child & Adolescent Hlth & Ageing, Ageing & Hlth Unit, Geneva, Switzerland
[7] WHO, Dept Global HIV Hepatitis & Sexually Transmitted I, Geneva, Switzerland
[8] Council Econ Hlth All, World Hlth Org Secretariat, Geneva, Switzerland