Funding for this research was provided by:
The Swedish Research Council for Health, Working Life and Welfare (2018-00384)
The Swedish Heart-Lung Foundation (20180636)
Received: 21 October 2020
Accepted: 22 April 2021
First Online: 6 May 2021
: All participants provided written (electronic 2014–2016 and on paper since 2017) informed consent prior to data collection. The study was approved by the Stockholm Ethics Review Board (Dnr 2015/1864–31/2 and 2016/9–32), and adhered to the Declaration of Helsinki.
: Not applicable.
: Gunnar Andersson and Peter Wallin are employed at HPI Health Profile Institute. The authors declare that they have no other competing interests.