The study was conducted in five HDSS which are part of the International Network for the Demographic Evaluation of Populations and Their Health in Low- and Middle-Income Countries (INDEPTH). The centres were Agincourt, South Africa (August 2008-February 2009); Ifakara, Tanzania (May 2009-December 2009); Iganga/Mayuge, Uganda (February 2009-October 2009); Kilifi, Kenya (conducted between December 2007-July 2008); Kintampo, Ghana (August 2010-April 2011)