Funding for this research was provided by:
Text and Data Mining valid from 2019-06-21
First Online: 21 June 2019
Compliance with Ethical Standards
: 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.
: It was obtained from all individual participants included in the study.