1. Department of Palliative Medicine, Beatson West of Scotland Cancer Centre, Glasgow, UK
2. Department of Physiotherapy, Beatson West of Scotland Cancer Centre, Glasgow, UK
3. Department of Pain Management, Stobhill Hospital, Glasgow, UK
4. Robertson Centre for Biostatistics, School of Health and Wellbeing, University of Glasgow, Glasgow, UK
5. Department of Pain Management, New Victoria Hospital, Glasgow, UK