Text and Data Mining valid from 2018-05-16
Received: 17 April 2017
Accepted: 4 May 2018
First Online: 16 May 2018
Ethics approval and consent to participate
: Kanton Zürich, Kantonale Ethikkommission, Stampfenbachstrasse 121, 8090 Zürich, Switzerland. IRB Nr: BASEC Nr: Req-2016-00442.All participants gave their written consent to this study.
: The authors declare that they have no competing interests.
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