1. Department of Public Health & Primary Care, Leiden University Medical Center, Hippocratespad 21 Postal zone V0-P, PO Box 9600, 2300 RC Leiden, The Netherlands
2. Stichting Florence, Nursing Home Mariahoeve, Hofzichtlaan 115, 2594 XZ The Hague, The Netherlands
3. Department of Epidemiology & Biostatistics, Amsterdam UMC, location VU University Amsterdam Public Health Research Institute, 1081 HV Amsterdam, The Netherlands