Text and Data Mining valid from 2019-11-23
Received: 4 April 2019
Accepted: 24 October 2019
First Online: 23 November 2019
Ethics approval and consent to participate
: The author(s) declare no conflict of interest. There was no funding in this study. The study was approved by the Ethics committee of Witten/Herdecke University and performed in accordance with the Declaration of Helsinki.
: Written informed consent from the legal parents on behalf of their child for the publication of this manuscript and any accompanying medical data was obtained. A copy of the written consent is available for review by the Editor-in-Chief of this journal.
: The authors declare that they have no competing interests.