Funding for this research was provided by:
Norges Blindeforbund (not applicable)
European Commission, Directorate - General Humanitarian Aid and Civil Protection (ECHO/SUB/2015/718665/PREP17)
Received: 14 August 2018
Accepted: 22 January 2019
First Online: 1 February 2019
Ethics approval and consent to participate
: The study was carried out anonymously and, at request, the Regional Committee for Medical and Health Research Ethics required no further formal ethical approval (Reference number: 2016/1615A). All participants provided informed consent for taking part in the study. Study participation was voluntary, and the participants were informed that they could withdraw from the study at any time.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.