WHAT DO CANNABIS USERS WITH PSYCHOSIS WANT FROM A PSYCHOLOGICAL INTERVENTION? A thesis submitted to The University of Manchester for the degree of Doctor of Clinical Psychology (ClinPsyD) In the Faculty of Biology, Medicine and Health 2016 Gemma Knight School of Health Sciences Division of Psychology and Mental Health University of Manchester Table of Contents List of Tables and Figures ................................................................................................................. 4 Thesis Abstract ..................................................................................................................................... 5 Declaration ............................................................................................................................................ 6 Copyright Statement ........................................................................................................................... 6 Acknowledgements ............................................................................................................................. 7 Paper 1: Systematic Review ............................................................................................................. 8 Abstract ................................................................................................................................................... 9 Introduction ....................................................................................................................................... 10 Method .................................................................................................................................................. 14 Eligibility criteria ......................................................................................................................... 14 Search procedures and data extraction ................................................................................ 15 Reliability ........................................................................................................................................ 16 Quality assessment ...................................................................................................................... 17 Results .................................................................................................................................................. 18 Overview of studies ..................................................................................................................... 18 To Escape from, or cope with, negative affect .................................................................... 22 To Enhance Positive Affect (Expansion/Intoxication) ..................................................... 29 Social Reasons (Enhancement, facilitation, belonging) .................................................. 32 Discussion ........................................................................................................................................... 35 References ........................................................................................................................................... 41 Paper 2: Empirical Paper ............................................................................................................... 45 Abstract ................................................................................................................................................ 46 Introduction ....................................................................................................................................... 46 Method .................................................................................................................................................. 48 Participants .................................................................................................................................... 48 Procedure ........................................................................................................................................ 49 Data Analysis .................................................................................................................................. 50 Results .................................................................................................................................................. 50 Quantitative data .......................................................................................................................... 51 Qualitative Data ............................................................................................................................ 51 Theme 1: Motivation to change behaviour ...................................................................... 52 Motivation to change cannabis use: “I’ve got to want to” ........................................... 52 Motivation to engage with services .................................................................................... 57 Theme 2: The ideal approach to treatment ..................................................................... 60 2 Preferred qualities of support ............................................................................................. 60 Preferred Treatment Outcomes .......................................................................................... 63 Discussion ........................................................................................................................................... 66 References ........................................................................................................................................... 72 Paper 3: Critical Reflection ............................................................................................................ 77 Introduction ....................................................................................................................................... 78 Paper 1: Systematic Review .......................................................................................................... 78 Rationale for topic selection ..................................................................................................... 78 Literature Search .......................................................................................................................... 78 Rationale for narrative synthesis ........................................................................................... 79 Quality Appraisal .......................................................................................................................... 79 Conducting the narrative synthesis ....................................................................................... 81 Limitations of the Narrative Synthesis .................................................................................. 81 Conclusions about paper 1 ........................................................................................................ 81 Paper 2: Empirical paper ............................................................................................................... 81 Rationale for topic ........................................................................................................................ 81 Rationale for methodology ....................................................................................................... 83 Recruitment ................................................................................................................................... 84 Participants .................................................................................................................................... 85 Measures ......................................................................................................................................... 86 Thematic Analysis ........................................................................................................................ 86 Limitations of methodology ...................................................................................................... 87 Conclusions about the empirical paper ................................................................................ 88 References ........................................................................................................................................... 89 Appendix .............................................................................................................................................. 91 Appendix A: Mixed Methods Appraisal Tool (MMAT) ...................................................... 91 Appendix B: MMAT Quality Appraisal Table ....................................................................... 99 Appendix C: Reasons for cannabis use data extraction table ........................................ 100 Appendix D: Substance Use Checklist .................................................................................. 104 Appendix E: The Reasons for Substance Use in Schizophrenia scale (ReSUS) ....... 105 Appendix F: Readiness to Change Questionnaire (RCQ) ............................................... 108 Appendix G: Ranking task treatment descriptions ......................................................... 109 Appendix H: Topic Guide ......................................................................................................... 114 Appendix I: Guide for Authors, Clinical Psychology Review