1. Department of Public Health, Faculty of Health, Aarhus University, Aarhus C, Denmark
2. Department of People and Technology, Roskilde University, Roskilde, Denmark
3. Department of Medical Science & Public Health, Bournemouth University, Bournemouth, Dorset, UK
4. Department of Health and Nursing Science, Faculty of Health and Sport Sciences, Agder University, Grimstad, Norway