1. Department of Old Age Psychiatry, Parnassia Psychiatric Institute, The Hague, The Netherlands
2. Department of Psychiatry, Leiden University Medical Center, Leiden, The Netherlands
3. Department of Psychiatry, Amsterdam University Medical Center, Vrije Universiteit Amsterdam, the Netherlands; GGZ Centraal, Hilversum, The Netherlands
4. Department of Psychiatry, University Medical Center Groningen (UMCG), Groningen, The Netherlands