Justin Grayer1
, John Cape2
, Lisa Orpwood3
, Judy Leibowitz4
and Marta Buszewicz5 
1Centre for Outcomes Research and Effectiveness (CORE), Sub-department of Clinical Health Psychology, University College London, 1-19 Torrington Place, London, WC1E 7HB, UK
2Camden and Islington NHS Foundation Trust, St Pancras Hospital, 4 St Pancras Way, London, NW1 0PE, UK
3Primary Care Mental Health Development Team, Islington PCT, 338-346 Goswell Road, London, EC1V 7LQ, UK
4Primary Care Mental Health Development Team, Camden PCT, Public Health Department, St Pancras Hospital, 4 St Pancras Way, London, NW1 0PE, UK
5Royal Free & University College Medical School, Research Department of Primary Care and Population Health, 2nd floor, Holborn Union Building, Archway Campus, Highgate Hill, London, N19 5LW, UK