Funding for this research was provided by:
Received: 5 September 2016
Accepted: 31 January 2018
First Online: 9 February 2018
Ethics approval and consent to participate
: This study was approved by the Regional Ethical Review Board at Lund University (application no. 2016/71). According to this consent the population was given the opportunity not to participate.
: Not Applicable.
: The authors declare that they have no competing interests.
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