Funding for this research was provided by:
GlaxoSmithKline Biologicals SA
Landspitali University Hospital Research Fund (B-2017-010)
Received: 20 February 2018
Accepted: 26 September 2018
First Online: 4 October 2018
Ethics approval and consent to participate
: The study was approved by The National Bioethics Committee (VSNb2013010015/03.07), the National Data Protection Authority (2013010100VEL/−−) and the Directorate of Health, Iceland (1,301,266/5.6.1/gkg). As this was a large epidemiological study where personal identifications were anonymised, obtaining informed consent was not required.
: Not applicable.
: The authors declare that they have no competing interests.
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