Randomised controlled trial of population screening for atrial fibrillation in people aged 70 years and over to reduce stroke: protocol for the SAFER trial oleh Gregory Y H Lip, Stephen Morris, Richard J McManus, Stephen Sutton, Howard Thom, Mark T Mills, Jonathan Mant, Simon J Griffin, Wern Yew Ding, Sarah Hoare, Jenni Burt, F D Richard Hobbs, Rachel Johnson, Mark Lown, Alison Powell, Natalie Armstrong, Martin Cowie, Trudie Lobban, Ben Freedman, Stephen Kaptoge, Jenny Lund, Duncan Edwards, Kate Williams, Andrew Dymond, Peter Calvert, Rakesh N Modi, Riccardo Proietti, Mike Sweeting