Received: 13 July 2018
Accepted: 11 December 2018
First Online: 22 December 2018
Ethics approval and consent to participate
: All research studies have been performed according to the rules of the local ethics committee of the University Medical Centre Hamburg-Eppendorf, Germany. All patient data were anonymized and evaluated in a retrospective design. Informed written consent was obtained from participants for research studies and presented data. In case of children under the age of 16 written informed consent was obtained from the parents.
: Not applicable.
: The authors declare that they have no competing interests.
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