Funding for this research was provided by:
Text and Data Mining valid from 2018-11-22
Received: 16 April 2018
Accepted: 31 October 2018
First Online: 22 November 2018
Ethics approval and consent to participate
: The study was approved by the regional ethical review board (EPN) in Malmö/ Lund, Sweden (2018/244). According to national regulations and guidelines, all samples analysed were anonymous and any connection with a particular patient could not be traced.
: Not applicable.
: The authors declare that they have no competing interests.
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