Glenn E Hunt1, Nandi Siegfried2, Kirsten Morley3, Thiagarajan Sitharthan1, Michelle Cleary4 1Discipline of Psychiatry, The University of Sydney, Sydney, Australia. 2Department of Psychiatry and Mental Health, University of  Cape Town, Cape Town, South Africa. 3Addiction Medicine, The University of Sydney, Sydney, Australia. 4School of Nursing and  Midwifery, University of Western Sydney, NSW, Australia Contact address: Glenn E Hunt, Discipline of Psychiatry, The University of Sydney, Concord Centrefor Mental Health, Hospital  Road, Sydney, NSW, 2139, Australia. glenn.hunt@sydney.edu.au.

Editorial group: Cochrane Schizophrenia Group. Publication status and date: Edited (no change to conclusions), published in Issue 4, 2014. Review content assessed as up-to-date: 15 January 2013. Citation: Hunt GE, Siegfried N, Morley K, Sitharthan T, Cleary M. Psychosocial interventions for people with both severe  mental illness and substance misuse. Cochrane Database of Systematic Reviews 2013, Issue 10. Art. No.: CD001088. DOI:  10.1002/14651858.CD001088.pub3. Copyright © 2014 The Cochrane Collaboration. Published by JohnWiley & Sons, Ltd.

A B S T R A C T Background Even low levels of substance misuse by people with a severe mental illness can have detrimental effects. Objectives To assess the effects of psychosocial interventions for reduction in substance use in people with a serious mental illness compared with  standard care. Search methods For this update (2013), the Trials Search Co-ordinator of the Cochrane Schizophrenia Group (CSG) searched the CSG Trials Register  (July 2012), which is based on regular searches of major medical and scientific databases. The principal authors conducted two further  searches (8 October 2012 and 15 January 2013) of the Cochrane Database of Systematic Reviews, MEDLINE and PsycINFO. A  separate search for trials of contingency management was completed as this was an additional intervention category for this update.  Selection criteria We included all randomised controlled trials (RCTs) comparing psychosocial interventions for substance misuse with standard care in  people with serious mental illness. Data collection and analysis We independently selected studies, extracted data and appraised study quality. For binary outcomes, we calculated standard estimates  of relative risk (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis. For continuous outcomes, we calculated  the mean difference (MD) between groups. For all meta-analyses we pooled data using a random-effects model. Using the GRADE  approach, we identified seven patient-centred outcomes and assessed the quality of evidence for these within each comparison.