Widerström-Noga, E
Biering-Sørensen, F
Bryce, T N
Cardenas, D D
Finnerup, N B
Jensen, M P
Richards, J S
Richardson, E J
Siddall, P J
Article History
Received: 22 December 2015
Revised: 25 February 2016
Accepted: 12 March 2016
First Online: 12 April 2016
Competing interests
: The authors declare no conflict of interest.