Pandyan Anand D, Radford Kate, Ashford Stephen, Bateman Andrew, Burton Christopher, Connell Louise, Gibson Alison, Harris Nigel, Hoffman Karen, Nair Roshan, Shaw Lisa, Turton Ailie, Tyson Sarah F, van Wijck Frederike
BMJ. 2013 Aug 6;347:f4876. doi: 10.1136/bmj.f4876.