Text and Data Mining valid from 2018-03-15
Received: 4 October 2017
Accepted: 9 March 2018
First Online: 15 March 2018
Ethics approval and consent to participate
: The ethical approval for this study was obtained from the ethical review committee (Ref. no. 2017–372-f-N), Ethikkommission der Ärztekammer Westfalen-Lippe und der Westfälischen Wilhelms-Universität, Münster, Germany.
: Not applicable.
: The authors declare that they have no competing interests.
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