Text and Data Mining valid from 2020-01-10
Received: 12 August 2019
Accepted: 31 December 2019
First Online: 10 January 2020
Compliance with ethical standards
: The authors report no conflict of interest.
: Institutional Review Board approval was granted before initiation of this study, and strict confidentiality guidelines were followed (Local Ethics Committee Reference Number EK 178/09).
: Participants provided informed written consent for the use of their results in this study and for publication at the time of enrolment.
: Written consent for publication was provided at the time of enrolment by the participants.