Text and Data Mining valid from 2018-06-26
Received: 25 January 2018
Accepted: 6 June 2018
First Online: 26 June 2018
Ethics approval and consent to participate
: The study was performed according to the Helsinki declaration and approved by the Regional Ethical Review Board in Stockholm, Sweden (Ref.nr. 2015/165–31/4) at 25 February 2015, and a completion of the ethics application (Ref.nr. 2017/1860–32) at 11 October 2017. (email: ExternalRef removed) Informed consent was waived because of the retrospective design of this study that did not involve any additional risk for patients.
: Not applicable.
: The authors declare that they have no competing interests.
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