Funding for this research was provided by:
Vinnvård Research Programme (A2008-025)
Text and Data Mining valid from 2018-04-02
Received: 12 June 2017
Accepted: 16 March 2018
First Online: 2 April 2018
Ethics approval and consent to participate
: All participation was based on written informed consent. Ethical approval was obtained from the Regional Ethical Committee in Umeå, Sweden (Dnr. 211–64-31 M).
: Not applicable.
: The authors declare that they have no competing interests.
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