1. Department of Internal Medicine , Section Gerontology and Geriatrics, , Leiden , the Netherlands
2. Leiden University Medical Center , Section Gerontology and Geriatrics, , Leiden , the Netherlands
3. LUMC Center for Medicine for Older People (LCO), Leiden University Medical Center , Leiden , the Netherlands
4. Department of Public Health and Primary Care, Leiden University Medical Center , Leiden , the Netherlands
5. KBO-PCOB , Nieuwegein , the Netherlands
6. Department of Geriatrics, Erasmus Medical Center , Rotterdam , the Netherlands