Braun, Tobias https://orcid.org/0000-0002-8851-2574
Thiel, Christian https://orcid.org/0000-0003-4507-8787
Schulz, Ralf-Joachim
Grüneberg, Christian https://orcid.org/0000-0001-8870-8457
Article History
Received: 23 July 2018
Accepted: 14 January 2019
First Online: 23 January 2019
Ethics approval and consent to participate
: The study was approved by 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.
: Not applicable.
: The authors declare that they have no competing interests.
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