Text and Data Mining valid from 2019-03-07
Received: 10 October 2018
Accepted: 25 February 2019
First Online: 7 March 2019
Ethics approval and consent to participate
: This investigation (including the survey) was performed with the approval of the regional Hannover Medical School ethics committee (N<sup>o</sup> 2065–2013). This article does not contain any studies with human subjects. The research described in the present manuscript was in accordance with both national law and the Helsinki Declaration of 1975 (including its most recently amended version). Informed consent was obtained from all individual participants included in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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