Text and Data Mining valid from 2018-09-03
Received: 19 February 2018
Accepted: 23 August 2018
First Online: 3 September 2018
Ethics approval and consent to participate
: Ethical approval for this study was obtained from the Ethics Committee of Medical Chamber Brandenburg (2016, No. S 7 (a)).Informed, written consent was obtained in advance from all study participants.
: Not applicable.
: The authors declare that they have no competing interests.
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