Funding for this research was provided by:
Zeidler-Forschungs-Stiftung, Waldkraiburg, Germany
Text and Data Mining valid from 2018-08-03
Received: 31 March 2018
Accepted: 26 July 2018
First Online: 3 August 2018
Ethics approval and consent to participate
: The study followed the Declaration of Helsinki on medical protocol and ethics and the regional Ethical Review Board of the technical university of Munich approved the study (approval number: 13/16 S).
: Written participant consent was obtained from the parents and the data collected were pseudonymized.
: The authors declare that they have no competing interests.
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