Funding for this research was provided by:
Region Jämtland Härjedalen (JLL-376981, JLL-377161)
Received: 11 May 2018
Accepted: 11 December 2018
First Online: 15 January 2019
Ethics approval and consent to participate
: The Regional Ethics Committee in Umeå approved the NAILED study on October 28, 2009 (Dnr 09-142 N). All participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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