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Article History

Received: 10 October 2018

Accepted: 13 February 2019

First Online: 21 March 2019

Ethics approval and consent to participate

: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Approval by the ethics committee was given in 03/2012 under project number 5295/12.

: Informed consent was obtained from all individual participants included in the study.

: The authors declare that they have no competing interests.

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