Funding for this research was provided by:
Text and Data Mining valid from 2019-03-12
Received: 15 April 2018
Accepted: 20 February 2019
First Online: 12 March 2019
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: Respondents provided written informed consent for participation. The study was approved by the ethics committee of Ludwig-Maximilians-Universitaet Munich (reference number 24–15).
: Respondents gave written informed consent for the publication of any findings from the analysis provided that their anonymity will be preserved.
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