Deding, Ulrik http://orcid.org/0000-0002-8263-2989
Henig, Anna Sharon
Torp-Pedersen, Christian
Bøggild, Henrik
Article History
Accepted: 18 October 2018
First Online: 1 November 2018
Compliance with ethical standards
: The current study was approved by the Danish Data Protection Agency (Ref. 2008-58-0028, 2016-34). All data in the study were linked and stored in computers held by Statistics Denmark. Data were made available with de-identified personal information. This study only publishes aggregated statistical analyses and results.
: The authors declare that they have no conflicts of interest.
: Retrospective anonymized register-based studies do not require written informed consent and ethical approval [CitationRef removed]. This article does not contain any studies with human participants or animals performed by any of the authors.