Nilsen, Roy M
Vik, Eline S
Rasmussen, Svein A
Small, Rhonda
Moster, Dag
Schytt, Erica
Aasheim, Vigdis
Article History
Received: 21 February 2018
Accepted: 27 September 2018
First Online: 26 October 2018
Ethics approval and consent to participate
: The study has been approved by the South East Regional Committees for Medical and Health Research Ethics in Norway (Folder number: 2014/1278). The approval includes the use of individual record linked data from the Medical Birth Registry of Norway (a national health registry) and Statistics Norway.
: Not applicable.
: The authors declare that they have no competing interests.
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