Funding for this research was provided by:
Forskningsrådet om Hälsa, Arbetsliv och Välfärd (2016-00081)
Fujian Medical University (XRCZX2020007, 2019QH1002)
Received: 28 February 2020
Accepted: 30 June 2020
First Online: 25 August 2020
Ethics approval and consent to participate
: The study was approved by the Regional Ethical Review Board in Stockholm (Dnr 2010/958-31/1, 2012/217/-32/2, and 2014/1401-32). KARMA participants consented to participate in the study with written informed consent.
: All authors approved the manuscript and consented to its publication.
: The authors declare no competing interest.