Funding for this research was provided by:
Received: 7 November 2018
Accepted: 31 May 2019
First Online: 20 June 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the University of Helsinki Review Board in humanities and social and behavioural sciences (REC number: #43/2016). Electronic informed consent was obtained from all individual participants included in the study and participation in the study was voluntary.
: Not applicable.
: The authors declare that they have no competing interests.