Received: 9 May 2017
Accepted: 21 February 2018
First Online: 5 March 2018
Ethics approval and consent to participate
: The Medical Ethics Committee of the Erasmus University Medical Center approved the ERF study protocol and all participants, or their legal representatives, provided written informed consent. Approval MEC 213.57512002.
: Not applicable.
: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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