Text and Data Mining valid from 2019-07-09
First Online: 9 July 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.• For this type of study, formal consent is not required.