1. Department of Rheumatology; University Hospitals Leuven; KU Leuven Belgium
2. Department of Rheumatology; University Hospital Gent; UGent Belgium
3. Department of Rheumatology; Cliniques universitaires Saint-Luc; Université catholique de Louvain; Brussels Belgium
4. Department of Public Health; Leuven Biostatistics and Statistical Bioinformatics Centre; Katholieke Universiteit Leuven; KU Leuven Belgium
5. Department of Nursing; University Hospitals Leuven; KU Leuven Belgium
6. Department of General Internal Medicine; University Hospitals Leuven; KU Leuven Belgium