Text and Data Mining valid from 2018-08-13
Received: 26 February 2018
Accepted: 16 July 2018
First Online: 13 August 2018
Compliance with Ethical Standards
: This study was not funded and there are no conflicts of interest to disclose.
: 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.