Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
↵* Information provided by author.
For correspondence: Dr M Vass, Institute of Public Health, University of Copenhagen, Copenhagen, Denmark.
Sources of funding: Danish Ministry of Social Affairs, Danish Medical Research Council, Research Foundation for General Practice and Primary Care, Eastern Danish Research Forum, and County Value-Added Tax Foundation.