Hinde, S
McKenna, C
Whyte, S
Peake, M D
Callister, M E J
Rogers, T
Sculpher, M
Article History
Received: 8 December 2014
Revised: 25 March 2015
Accepted: 7 April 2015
First Online: 26 May 2015
Competing interests
: The authors declare no conflict of interest.