Funding for this research was provided by:
Erasmus Mundus (3, 4)
Received: 19 January 2018
Accepted: 14 May 2018
First Online: 23 June 2018
Ethics approval and consent to participate
: Written informed consent was obtained from all participants before inclusion in the study. The medical ethics committee approved the study.
: The authors declare that they have no competing interests.
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