Funding for this research was provided by:
Received: 21 November 2017
Accepted: 19 March 2018
First Online: 27 March 2018
Ethics approval and consent to participate
: Ethical approval for this study was asked and waived the local Medical Research Ethics Committee, region Arnhem-Nijmegen (protocol number 2013/292) and the Medical Ethics Review Committee of the University Medical Centre, Leiden (protocol number: P13.202). All participants gave written consent to participate in the present study.
: Not applicable.
: The authors declare that they have no competing interests.
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