Smed, S
Scarborough, P
Rayner, M
Jensen, J D
Article History
Received: 30 April 2015
Revised: 1 December 2015
Accepted: 16 January 2016
First Online: 13 April 2016
Competing interests
: None of the authors have financial relationships with any organisation that might have had an interest in the submitted work in the previous 3 years and no other relationships or activities that could appear to have influenced the submitted work. The authors declare no conflict of interest.