1. School for Oncology and Developmental Biology (GROW), Department of Epidemiology; Maastricht University Medical Center; Maastricht; The Netherlands
2. Department of Prevention and Health; TNO Quality of Life; Leiden; The Netherlands
3. School for Oncology and Developmental Biology (GROW), Division of Hematology, Department of Internal Medicine; University Hospital Maastricht; Maastricht; The Netherlands