Text and Data Mining valid from 2019-03-13
Received: 4 January 2019
Accepted: 12 February 2019
First Online: 13 March 2019
Compliance with Ethical Standards
: All the authors declare they have no competing interest.
: Informed consent was obtained from all individual participants in the study.
: All procedures performed in the study were in accordance with the ethical standards of the institution.