Funding for this research was provided by:
Norwegian Ministry of Justice and Public Security (Not applicable)
Norges Forskningsråd (256678)
Received: 20 May 2017
Accepted: 10 April 2018
First Online: 17 April 2018
: AS is a Senior Researcher at Statistics Norway, focusing on inequalities in health, morbidity and mortality. She holds a PhD in community medicine. MTD is a Senior Advisor and responsible for immigration statistics at Statistics Norway. She holds detailed knowledge of the data sources used, including their strengths and weaknesses. BNK is a MD/PHD. She is a Researcher at the Norwegian Centre for Migration and Health (NAKMI), at the Norwegian Institute of Public Health (NIPH), and an Associate Professor at the Department of Global Health at the University of Oslo. ED is a MD/PhD with a specialization in Family Medicine. She is the Deputy Director of NAKMI, NIPH, and is an Associate Professor at the Department for Global Public Health and Primary Care at the University of Bergen.
: The data linkage and analyses have been conducted in accordance with the Norwegian 1989 Statistics Act, §3–1 c, conf. §§ 1–1 and 2–2, and has been approved by the Norwegian Board of Ethics. As only administrative data were used, the Norwegian Board of Ethics waived the need for informed consent. The research was carried out in compliance with the Helsinki Declaration.
: The authors declare that they have no competing interests.
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