Funding for this research was provided by:
Fresenius Medical Care
Received: 12 August 2017
Accepted: 2 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: Ethics approval was obtained from the local ethics committee. Written informed consent was obtained either from the patient or their appointed legal guardian.
: Not applicable.
: The authors declare that they have no competing interests.
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