Text and Data Mining valid from 2019-05-09
Received: 18 November 2018
Accepted: 25 April 2019
First Online: 9 May 2019
Ethics approval and consent to participate
: The study was approved by the local ethics committee of Zurich (protocol number: KEK-ZH-Nr. 2017–00500).
: Not applicable.
: The authors declare that they have no competing interests.
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