Text and Data Mining valid from 2019-02-10
Received: 17 September 2018
Accepted: 28 January 2019
First Online: 10 February 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: All investigations were conducted in conformity with ethical principles of research and that institutional approval of the human protocol for this investigation was obtained.
: Informed consent for participation in the study was obtained.