Funding for this research was provided by:
Carl Wilhelm Scheele
Received: 26 July 2016
Accepted: 15 January 2018
First Online: 24 January 2018
Ethics approval and consent to participate
: The regional ethics committee in Umeå approved this study 11 November 2014 (reference code 2014/322-31Ö). Written consent was obtained from all study participants.
: Not applicable.
: The authors declare that they have no competing interests.
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