Text and Data Mining valid from 2018-10-22
Received: 14 August 2018
Revised: 20 September 2018
Accepted: 26 September 2018
First Online: 22 October 2018
Compliance with ethical standards
: All procedures performed in this study were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this study, formal consent was obtained.
: Informed consent was obtained from all individual participants included in the study.
: The authors declare that they have no conflict of interest.