Text and Data Mining valid from 2019-03-23
Received: 12 September 2018
Accepted: 13 March 2019
First Online: 23 March 2019
Ethics approval and consent to participate
: The ethical approval for this study was obtained from the ethical review committee (Ref. no. 2016–006-f-S), Ethikkommission der Ärztekammer Westfalen-Lippe und der Westfälischen Wilhelms-Universität, Münster, Germany. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: The authors declare that they have no competing interests.
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