Text and Data Mining valid from 2020-04-09
Received: 29 October 2019
Accepted: 6 March 2020
First Online: 9 April 2020
Ethics approval and consent to participate
: All procedures performed in this study were in accordance with the ethical standards of the ethic committee of Zurich, the 1964 Helsinki declaration and its later amendments.
: Informed consent was obtained from all the individual participants included in the study.
: To the best of our knowledge not applicable.