Text and Data Mining valid from 2019-06-11
Received: 28 February 2019
Accepted: 31 May 2019
First Online: 11 June 2019
Ethics approval and consent to participate
: The research was approved by the Regional Ethical Review Board in Gothenburg (no: 644–2008). Informed consent of participants was not required as the retrospective study design did not affect the health care of included patients.
: Not applicable.
: The authors declare that they have no competing interests.