Text and Data Mining valid from 2019-11-04
Received: 1 October 2019
Accepted: 30 October 2019
First Online: 4 November 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: All procedures in this study involving human participants were in accordance with the ethical standards of the institutional committee and with the 1964 Helsinki Declaration and its later amendments.
: Informed consent was obtained from all individual participants included in the study.