Text and Data Mining valid from 2018-12-06
Received: 17 August 2018
Accepted: 29 November 2018
First Online: 6 December 2018
Compliance with ethical standards
: Informed consent was obtained from all individual participants included in the study.
: 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.
: The authors declare that they have no conflict of interest.