. 2014 Feb 17;101(4):417–423. doi: 10.1002/bjs.9388
© 2014 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.