Funding for this research was provided by:
Helse Sør-Øst RHF (2014064)
Received: 11 July 2019
Accepted: 29 November 2019
First Online: 13 February 2020
Ethics approval and consent to participate
: The Norwegian Ethics Committee and the Norwegian Data Protection Authority, in addition to all the registry owners, approved this study. Registry owners gave us administrative permission to access and use the data. Registry owners include the Norwegian Directorate of health (NPR [CitationRef removed], KUHR [CitationRef removed], IPLOS [CitationRef removed]), the Cancer Registry of Norway [CitationRef removed], the National Institute of Public Health (the Norwegian Causes of Death Register [CitationRef removed]), and Statistics Norway (SSB, ExternalRef removed).
: Not applicable.
: The authors declare that they have no competing interests.