Funding for this research was provided by:
Eesti Teadusfondi (ETF4350)
Haridus- ja Teadusministeerium (IUT34–17)
Eesti Teadusagentuur (ETF8523)
Received: 22 October 2019
Accepted: 29 January 2020
First Online: 3 February 2020
Ethics approval and consent to participate
: ECRHS and SOHOS study was approved by University of Tartu Centre of Ethics.
: Not applicable.
: The authors declare that they have no competing interests.