Funding for this research was provided by:
Text and Data Mining valid from 2019-11-13
First Online: 13 November 2019
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study. The informed consent was part of the first page of the online-survey. Every participant could choose, whether he/she wants to participate in the study or not. No identifying information about participants was collected.