1. Department of Primary and Community Care, Radboud University Medical Center, Nijmegen, the Netherlands
2. Department of Pathology, Maastricht University, Maastricht, the Netherlands
3. Department of Family Medicine, Maastricht University, Maastricht, the Netherlands
4. Network of GP Specialty Training Institutes, Utrecht, the Netherlands
5. Department of General Practice and Elderly Care Medicine, University Medical Centre Groningen, Groningen, the Netherlands