Text and Data Mining valid from 2020-04-07
Received: 22 January 2020
Accepted: 28 March 2020
First Online: 7 April 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Riga Stradins University, Riga, Latvia (No. 8/18.06.2015.). The project was carried out in accordance with the Declaration of Helsinki and its subsequent amendments. All respondents were enrolled only after providing written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.