Text and Data Mining valid from 2019-04-08
Received: 6 August 2018
Accepted: 25 March 2019
First Online: 8 April 2019
Compliance with ethical standards
: 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 conflicts of interest.
: Informed consent was obtained from all individual participants included in the study.