Received: 31 January 2017
Accepted: 15 November 2018
First Online: 6 December 2018
Ethics approval and consent to participate
: Danish legislation does not require ethical approval for register studies according to “Guidelines about Notification etc. of a Biomedical Research Project” Law no. 593, 14 June 2011 [CitationRef removed]. Section 2.7 states, “<i>A register research project where only information in the form of sign-based symbols, including figures, letters, etc. is applied shall not be notified to research ethics committees.</i>” [CitationRef removed].The study was approved by the Danish Data Protection Agency (j.nr. 2014-41-2928) and The Danish Health and Medicines Authority j.nr. 3–3013-582/1/.Approval for the study was also granted by the relevant authorities at the hospital.
: Not applicable.
: The authors declare that they have no competing interests.
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