1. Department of Materials and Production, Aalborg University, Fibigerstraede 16, 9220 Aalborg East, Denmark
2. Department of Public Health, Aarhus University, Bartholins Allé 2, 8000 Aarhus, Denmark
3. Research Unit for General Practice, Aarhus University, Bartholins Allé 2, 8000 Aarhus, Denmark
4. Department of Mathematical Sciences, Aalborg University, Skjernvej 4A, 9220 Aalborg East, Denmark