Braun, Tobias http://orcid.org/0000-0002-8851-2574
Grüneberg, Christian
Thiel, Christian http://orcid.org/0000-0003-4507-8787
Schulz, Ralf-Joachim
Article History
Received: 12 October 2017
Accepted: 3 April 2018
First Online: 23 April 2018
Ethics approval and consent to participate
: The study was approved by the Ethical Review board of the Ethical Review board of the University of Cologne. Ongoing, written informed consent was provided by all participants. Guardian informed consent was approved if necessary.
: The authors declare that they have no competing interests.
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