1. Department of General Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
2. Department of Internal Medicine, Diakonessenhuis, Utrecht, the Netherlands
3. Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands
4. Department of Internal Medicine, Leyenburg Hospital, the Hague, the Netherlands
5. Department of Biostatistics, Leiden University Medical Center, Leiden, the Netherlands