1. Department of Rheumatology, Leiden University Medical Center, the Netherlands
2. Department of Psychiatry, Leiden University Medical Center, the Netherlands
3. Department of Psychiatry, Haaglanden Medical Center, the Hague, the Netherlands
4. Department of Neurology Leiden University Medical Center, the Netherlands
5. Department of Psychology, Health, Medical and Neuropsychology Unit, Leiden University, the Netherlands
6. Department of Clinical Epidemiology, Leiden University Medical Center, the Netherlands
7. Department of Rheumatology, Haaglanden Medical Center, the Hague, the Netherlands