Funding for this research was provided by:
Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (01ER1302, 01ER1702)
Text and Data Mining valid from 2019-04-24
Received: 8 February 2019
Accepted: 8 April 2019
First Online: 24 April 2019
Ethics approval and consent to participate
: The study was approved by the Medical Ethics Review Board of the Medical Faculty Mannheim at Heidelberg University (2015-550 N-MA) and the Ethics Committee of the Federal Physician Chamber of Hesse (MC180/2015). Written informed parental/legal guardian consent was provided on behalf of any and all underage participants.
: Not applicable.
: The authors declare that they have no competing interests.
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