1. NIVEL, Netherlands Institute of Health Services Research; P.O. Box 1568 3500 BN Utrecht The Netherlands
2. Koraalgroep, Maasveld; P.O. Box 1045 6201BA Maastricht The Netherlands
3. Department of General Practice & Elderly Care Medicine; EMGO Institute for Health and Care Research; VU University Medical Center; P.O. Box 7057 1007 MB Amserdam The Netherlands
4. Expertise Center for Palliative Care Amsterdam; VU University Medical Center; Amsterdam The Netherlands
5. Department of Public and Occupational Health; EMGO Institute for Health and Care Research; VU University Medical Center; P.O. Box 7057 1007 MB Amserdam The Netherlands