1. Centre for Pain Research; University of Bath; Bath UK
2. Cochrane Pain, Palliative and Supportive Care Group; Pain Research Unit, Churchill Hospital; Oxford UK
3. School of Social and Community Medicine; University of Bristol; Bristol UK
4. Cochrane Pain, Palliative and Supportive Care Group, Pain Research Unit; Churchill Hospital; Oxford UK
5. Oxford UK
6. NHS Gloucestershire CCG; Brockworth UK
7. School of Pharmacy; University of Nottingham; Nottingham UK
8. Plymouth UK