University College London, University College London - Department of Clinical, Educational and Health Psychology, University College London, University College London, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, University College London, University College London, University College London, Harrow and Hillingdon Early Intervention in Psychosis, Harrow and Hillingdon Early Intervention in Psychosis, Harrow and Hillingdon Early Intervention in Psychosis, affiliation not provided to SSRN, Harrow and Hillingdon Early Intervention in Psychosis, Harrow and Hillingdon Early Intervention in Psychosis, University of East London, affiliation not provided to SSRN, affiliation not provided to SSRN, Harrow and Hillingdon Early Intervention in Psychosis, Harrow and Hillingdon Early Intervention in Psychosis, University College London and Harrow and Hillingdon Early Intervention in Psychosis