Funding for this research was provided by:
Svenska Forskningsrådet Formas (2013-11988-25343-43)
Text and Data Mining valid from 2018-04-11
Received: 9 November 2017
Accepted: 3 April 2018
First Online: 11 April 2018
Ethics approval and consent to participate
: The regional ethical review board at Umeå University, Sweden granted ethical approval. Informed consent was given by the study participants.
: The authors declare that they have no competing interests.
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