Affiliation: | 1. Division of Drug Research, Department of Medical and Health Sciences, Faculty of Health Sciences, Link?ping University, , County Council of ?sterg?tland, Sweden;2. Nordic School of Public Health NHV, , Gothenburg, Sweden;3. Unit of Social Medicine, University of Gothenburg, , Gothenburg, Sweden;4. Centre for Applied Biostatistics, University of Gothenburg, , Gothenburg, Sweden |