Text and Data Mining valid from 2019-11-06
Received: 15 July 2019
Accepted: 21 October 2019
First Online: 6 November 2019
Compliance with ethical standards
: The authors declare they have no conflicts of interest.
: All procedures performed in the study involving human participants are in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its subsequent amendments or comparable ethical standards.
: Informed consent was individually obtained from all participants included in the study.