Funding for this research was provided by:
Eesti Teadusagentuur (IUT5-1)
Text and Data Mining valid from 2018-12-01
Received: 8 July 2018
Accepted: 16 November 2018
First Online: 3 December 2018
Ethics approval and consent to participate
: All surveys have been performed in accordance with the Declaration of Helsinki and were approved by the respective national ethics review boards, that is, the Tallinn Medical Research Ethics Committee in Estonia and the Lithuanian Bioethics Committee in Lithuania. In this study, only anonymous secondary data were used.
: Not applicable.
: The authors declare that they have no competing interests.
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