Authors: Paula Mulvenna; Matthew Nankivell; Rachael Barton; Corinne Faivre-Finn; Paula Wilson; Elaine McColl; Barbara Moore; Iona Brisbane; David Ardron; Tanya Holt; Sally Morgan; Caroline Lee; Kathryn Waite; Neil Bayman; Cheryl Pugh; Benjamin Sydes; Richard Stephens; Mahesh K Parmar; Ruth E Langley Journal: Lancet Date: 2016-09-04 Impact factor: 79.321