Text and Data Mining valid from 2019-11-27
Received: 19 August 2019
Accepted: 5 November 2019
First Online: 27 November 2019
Ethics approval and consent to participate
: The study was approved by the local Research Ethics Committee, and all participants gave their written informed consent according to the Declaration of Helsinki.
: All participants gave their written informed consent for the anonymous publication of their data.
: The authors declare that they have no competing interests.