Funding for this research was provided by:
Fonds Wetenschappelijk Onderzoek (11ZI716N, G0E1614N)
Text and Data Mining valid from 2018-04-13
Received: 13 October 2017
Accepted: 5 April 2018
First Online: 13 April 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: All procedures performed in this study have been approved by the University of Antwerp ethical committee (file number 2013-73) and the University of Groningen ethical committee (file number 6986/6986A).