Funding for this research was provided by:
County Council of Östergötland, Sweden/Region Östergötland (LIO-439131)
Medical Research of Southeast Sweden/Forskningsrådet i Sydöstra Sverige (FORSS-475291)
Received: 28 June 2017
Accepted: 16 April 2018
First Online: 5 June 2018
Ethics approval and consent to participate
: The study was approved by the Regional Ethical Review Board in Linköping, Sweden (code 2013/223-31). The study was carried out in accordance with the Declaration of Helsinki. Written informed consent was obtained from all individual participants included in the study.
: The authors declare that they have no competing interests.
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