Luijks, Hilde D
de Grauw, Wim JC
Bor, Jacobus HJ
van Weel, Chris
Lagro-Janssen, Antoine LM
Biermans, Marion CJ
Schermer, Tjard R
Article History
Received: 31 July 2014
Revised: 12 January 2015
Accepted: 10 February 2015
First Online: 23 April 2015
Competing interests
: The authors declare no conflict of interest.