Authors: Anoop S V Shah; Megan Griffiths; Kuan Ken Lee; David A McAllister; Amanda L Hunter; Amy V Ferry; Anne Cruikshank; Alan Reid; Mary Stoddart; Fiona Strachan; Simon Walker; Paul O Collinson; Fred S Apple; Alasdair J Gray; Keith A A Fox; David E Newby; Nicholas L Mills Journal: BMJ Date: 2015-01-21