Text and Data Mining valid from 2018-06-15
Received: 6 April 2018
Accepted: 27 May 2018
First Online: 15 June 2018
Ethics approval and consent to participate
: This study was approved with the need for individual patient consent waived by the West of Scotland research ethics committee due to its retrospective observational nature.
: The authors declare that they have no competing interests.
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