1. Institute of Primary Care and Public Health, Cardiff University, Cardiff, UK (NJ-W, RN, AE, GE)
2. Division of Public Health Sciences, Department of Surgery, Washington University School of Medicine, St. Louis, MO (MP)
3. Department of Psychology, University of Hertfordshire, Hatfield, UK (M-AD)
4. Marie Curie Palliative Care Research Centre, Wales Cancer Trials Unit, Cardiff University, Cardiff, UK (SS)
5. Faculty of Health Sciences, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada (DS, CB)