Text and Data Mining valid from 2018-09-01
Accepted: 30 August 2018
First Online: 1 September 2018
Compliance with ethical standards
: All authors declare that they have no conflict of interest.
: 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.
: Informed consent was obtained from all individual participants included in the study.