Funding for this research was provided by:
Received: 25 October 2017
Accepted: 6 August 2018
First Online: 14 August 2018
Ethics approval and consent to participate
: The study protocol is approved by the Medical Ethical Committee of the University Medical Centre Groningen, the Netherlands (Ref No: NL58022.042.16, 2016/334).Written informed consent to participate is obtained from all participants and/or their legal representatives.
: Not applicable
: The authors declare that they have no competing interests.
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