Funding for this research was provided by:
Haridus- ja Teadusministeerium (IUT34-17)
Text and Data Mining valid from 2019-03-14
Received: 25 September 2018
Accepted: 6 March 2019
First Online: 14 March 2019
Ethics approval and consent to participate
: This study was approved by the Research Ethics Committee of the University of Tartu (260/T-24). This was a registry-based study; for this type of study informed consent is not required. Estonian Data Protection Inspectorate’s approval (2.2-1/16/15) was secured prior to the implementation of the research.
: Not applicable.
: The authors declare that they have no competing interests.
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