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Article History

Received: 3 May 2018

Accepted: 27 December 2018

First Online: 9 January 2019

Ethics approval and consent to participate

: An ethical statement for this study was not required since the criteria for such a statement were not fulfilled (for instance, examination of patients, risk for the respondents, lack of information about the goals of the study, use of invasive methods).Prior to the interview, written informed consent was given by all participants of the study.

: Not applicable.

: The authors declare that they have no competing interests.

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