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Article History

Received: 20 January 2018

Accepted: 25 April 2018

First Online: 3 May 2018

Ethics approval and consent to participate

: The study has been approved by the ethics committee (Ethikkommission der Charité – Universitätsmedizin Berlin; vote, EA2/151/16), and all subjects (or the person having the care and custody of the child) signed an informed consent form regarding the participation in the study and a consent for publication.

: All subjects (or the person having the care and custody of the child) signed an informed consent form regarding the consent for publication.

: The authors declare that they have no competing interests.

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