1. Warwick Medical School, University of Warwick; Warwick Clinical Trials Unit; Gibbet Hill Road Coventry UK CV4 7AL
2. Institute of Psychiatry (King's College London); National Addiction Centre; 4 Windsor Walk, Camberwell London England UK
3. Oxford Brookes University; School of Health and Social Care; Jack Straws Lane Marston Oxford UK OX3 0FL