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Article History

Received: 4 August 2017

Accepted: 8 January 2018

First Online: 23 January 2018

Ethics approval and consent to participate

: The ethics committee of the University Medicine Greifswald approved the study (BB 002/15a). All participants provided informed written consent prior to participation.

: All participants provided written consent that was based on study information sheet which included the statement that all scientific publications will not include personal data (e.g., name, birth date, and address).

: The authors declare that they have no competing interests.

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