University of Southampton Research Repository ePrints Soton Copyright © and Moral Rights for this thesis are retained by the author and/or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder/s. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given e.g. AUTHOR (year of submission) "Full thesis title", University of Southampton, name of the University School or Department, PhD Thesis, pagination http://eprints.soton.ac.uk UNIVERSITY OF SOUTHAMPTON FACULTY OF SOCIAL AND HUMAN SCIENCES Psychology Acceptance and Commitment Therapy: Cognitive Fusion and Personality Functioning by Helen Bolderston Thesis for the degree of Doctor of Philosophy May 2013 UNIVERSITY OF SOUTHAMPTON ABSTRACT FACULTY OF SOCIAL AND HUMAN SCIENCES PSYCHOLOGY Doctor of Philosophy ACCEPTANCE AND COMMITMENT THERAPY: COGNITIVE FUSION AND PERSONALITY FUNCTIONING by Helen Bolderston Personality disorders (PDs) are common, chronic, mental health problems. The majority of treatment outcome research, which has focused specifically on Borderline PD, has provided substantial empirical support for Dialectical Behaviour Therapy (DBT; Linehan, 1993), particularly in terms of self-harm reduction. Nevertheless, DBT graduates can continue to experience poor personality functioning across PD diagnostic categories, Axis I disorders, and restricted lives. Acceptance and Commitment Therapy (ACT; Hayes, Strosahl, & Wilson, 1999), might be suitable as a follow-up intervention for DBT graduates, to address their continued difficulties: to date, however, there has been little empirical investigation of its utility in relation to PD. This thesis was therefore designed to examine theoretical underpinnings of ACT relevant to the development of an ACT intervention for DBT graduates. Study 1 tested the performance of a new self-report measure of cognitive fusion (CF), the Cognitive Fusion Questionnaire (CFQ), with a mental health sample, including individuals with PD. CF is a key ACT concept, and the CFQ proved to be a psychometrically sound measure of CF with people with mental health problems. Study 2 used cross-sectional modelling to show that CF fully mediated the relationships between two PD risk factors, negative affectivity and childhood trauma, and personality functioning in adulthood. Study 3 used the CFQ to investigate the behavioural correlates of CF. These findings strengthened the possibility that an ACT-based intervention might prove effective in improving outcomes for DBT graduates. To explore this further, Studies 4 and 5 were designed as very small-scale uncontrolled treatment development trials for this population. Study 4 suggested that ACT had a positive impact on engagement in life, but produced little improvement in psychiatric symptomology. Study 5 tested a revised protocol, which yielded more consistently positive findings, with improvements in both engagement in life and psychiatric symptoms. These findings tentatively suggest that ACT may have a role to play as a DBT follow-up intervention. i TABLE OF CONTENTS DECLARATION OF AUTHORSHIP ................................................................................. vii ACKNOWLEDGEMENTS ................................................................................................. viii CHAPTER I .................................................................................................................. 1 Personality Disorder ................................................................................................................ 1 1.1 Diagnosis ......................................................................................................................... 1 1.1.1 Comorbidity and Dimensionality in PDs ............................................................................... 2 1.2 Aetiology of PD .............................................................................................................. 4 1.3 Treatment of PD .............................................................................................................. 6 1.3.1 Psychosocial Treatment of PD ............................................................................................... 6 1.3.2. Behavioural and Cognitive Behavioural Psychotherapies .................................................... 7 1.3.2.1 Behaviour Therapy .............................................................................................................. 8 1.3.2.2 Cognitive Behaviour Therapy ............................................................................................. 9 1.3.2.3 Dialectical Behaviour Therapy .......................................................................................... 11 1.3.3 Psychodynamic and Interpersonal Psychotherapies ............................................................. 19 1.3.3.1 Cognitive Analytic Therapy .............................................................................................. 20 1.3.3.2 Schema Therapy ................................................................................................................ 21 1.3.3.3 Psychodynamic Psychotherapy ......................................................................................... 22 1.3.4 General Discussion of Psychosocial Treatment Literature .................................................. 24 CHAPTER II .............................................................................................................. 29 Behavioural and Cognitive Behavioural Psychotherapies ................................................. 29 2.1 First and Second Wave Behavioural and Cognitive Behavioural Psychotherapies ...... 29 2.2 Third Wave Psychotherapies ......................................................................................... 32 2.2.1 Acceptance and Commitment Therapy ................................................................................ 33 2.2.1.1 Relational Frame Theory ................................................................................................... 33 2.2.1.2 Psychological Inflexibility Model ..................................................................................... 36 2.2.1.3 ACT: Therapeutic Features ............................................................................................... 46 2.2.1.4 Evidence Supporting ACT: Outcome and Process Findings ............................................ 48 CHAPTER III ............................................................................................................. 53 Methodological Considerations ............................................................................................ 53 3.1 Preclinical or Theoretical Phase .................................................................................... 53 3.2 Phase I: Modelling ........................................................................................................ 55 3.2.1 Measurement ........................................................................................................................ 55 3.2.2 Model Building and Testing ................................................................................................. 64 3.3 Phase II: Exploratory Trial ............................................................................................ 73 3.3.1 Statistical Considerations in Small-Scale, Open Trials ........................................................ 74 3.3.2 RCTs .................................................................................................................................... 75 3.3.3 Statistical Considerations in RCTs ....................................................................................... 76 3.4 Phase III: Definitive RCT ............................................................................................. 78 3.5 Phase IV: Long-Term Implementation ......................................................................... 78 3.6 The Present Thesis ........................................................................................................ 80 CHAPTER IV ............................................................................................................. 83 Study 1. The Clinical Validation of a Self-Report Measure of Cognitive Fusion ............ 83 4.1 Introduction ................................................................................................................... 83 4.1.1 Cognitive Fusion .................................................................................................................. 83 4.1.2 Measurement of Cognitive Fusion ....................................................................................... 84 4.1.3 Cognitive Fusion Questionnaire ........................................................................................... 85 4.1.4 Present Study ........................................................................................................................ 88 4.2 Method .......................................................................................................................... 89 4.2.1 Participants ........................................................................................................................... 89 4.2.2 Materials ............................................................................................................................... 91 4.2.3 Procedure .............................................................................................................................. 94 ii 4.2.4 Analysis Plan ....................................................................................................................... 95 4.3 Results ........................................................................................................................... 95 4.3.1 Data Screening ..................................................................................................................... 95 4.3.2 Stage One: Item Characteristics, Distribution and Outliers ................................................ 96 4.3.3 Stage Two: Confirmatory Factor Analysis .......................................................................... 98 4.3.4 Stage Three: Reliability ..................................................................................................... 100 4.3.5 Sample Characteristics ...................................................................................................... 101 4.3.6 Concurrent, Convergent, and Divergent Validity .............................................................. 102 4.4 Discussion ................................................................................................................... 105 4.4.1 Study Findings ................................................................................................................... 105 4.4.2 Methodological Limitations .............................................................................................. 108 4.4.3. Future Research ................................................................................................................ 109 4.4.4 Summary ............................................................................................................................ 110 CHAPTER V ............................................................................................................ 111 Study 2. Modelling the Role of Cognitive Fusion in Relation to Personality Functioning .......................................................................................................................... 111 5.1 Introduction ................................................................................................................. 111 5.1.1 Risk Factors for Poor Personality Functioning .................................................................. 112 5.1.2 The Role of Cognitive Fusion ........................................................................................... 112 5.1.3 Study Synopsis, Methodological and Design Considerations ........................................... 114 5.2 Method ........................................................................................................................ 115 5.2.1 Design ................................................................................................................................ 115 5.2.2 Participants ........................................................................................................................ 115 5.2.3 Materials ............................................................................................................................ 116 5.2.4 Procedure ........................................................................................................................... 118 5.2.5 Analysis Plan ..................................................................................................................... 119 5.3 Results ......................................................................................................................... 119 5.3.1 Stage One: Data Screening and Preliminary Analyses ...................................................... 119 5.3.2 Stage Two: Mediational Analyses ..................................................................................... 122 5.3.3 Stage Three. SEM Mediational Models ............................................................................ 125 5.4 Discussion ................................................................................................................... 129 5.4.1 Study Findings ................................................................................................................... 129 5.4.2 Methodological Limitations .............................................................................................. 132 5.4.3 Implications and Future Research ..................................................................................... 133 5.4.4 Summary ............................................................................................................................ 135 CHAPTER VI ........................................................................................................... 137 Study 3: An Investigation of the Behavioural Correlates of Cognitive Fusion ............. 137 6.1 Introduction ................................................................................................................. 137 6.1.1 Laboratory-Based Investigation of Cognitive Fusion ....................................................... 137 6.1.2 Cognitive Fusion and Experiential Avoidance .................................................................. 138 6.1.3 Measuring Experiential Avoidance ................................................................................... 140 6.1.4 Study Design, Aims, and Hypotheses ............................................................................... 142 6.2 Method ........................................................................................................................ 143 6.2.1 Participants ........................................................................................................................ 143 6.2.2 Materials ............................................................................................................................ 143 6.2.3 Procedure ........................................................................................................................... 145 6.2.4 Analysis Plan ..................................................................................................................... 146 6.3 Results ......................................................................................................................... 147 6.3.1 Stage One. Data Screening and Preliminary Analyses ...................................................... 147 6.3.2 Stage Two. Comparisons between view time for positively and negatively valenced words. ......................................................................................................................................... 149 6.3.3 Stage Three. Relationship Between CFQ Score and Stimulus View Time. ...................... 149 6.3.4 Memory Data Analysis ...................................................................................................... 150 6.4 Discussion ................................................................................................................... 150 6.4.1 Study Findings ................................................................................................................... 150 6.4.2 Methodological Limitations .............................................................................................. 154 6.4.3 Implications and Future Research ..................................................................................... 156 iii 6.4.4. Summary ........................................................................................................................... 158 Chapter VII ............................................................................................................... 159 Study 4: Uncontrolled pilot development trial of an ACT-based group intervention for post-DBT patients with poor personality functioning ...................................................... 159 7.1 Introduction ................................................................................................................. 159 7.1.1 DBT and PD ....................................................................................................................... 160 7.1.2 ACT Processes and Personality Functioning ..................................................................... 160 7.1.3 ACT-Based Interventions for PD ....................................................................................... 161 7.1.4 Methodological Considerations .......................................................................................... 162 7.2 Method ........................................................................................................................ 164 7.2.1 Design ................................................................................................................................ 164 7.2.2 Participants ......................................................................................................................... 164 7.2.3 Materials ............................................................................................................................. 168 7.2.4 Procedure ............................................................................................................................ 171 7.2.5 Analysis Plan ...................................................................................................................... 180 7.3 Results ......................................................................................................................... 180 7.3.1 Stage One. Preliminary Analysis and Participant Characteristics ...................................... 180 7.3.2 Stage Two. Group statistical analyses ................................................................................ 181 7.3.3 Stage Three. Reliable and Clinically Significant Individual Changes ............................... 183 7.3.4 Stage Four. Data Not Analysed Using the RCI Methodology ........................................... 188 7.4 Discussion ................................................................................................................... 191 7.4.1 Study Findings ................................................................................................................... 191 7.4.2 Methodological Limitations ............................................................................................... 197 7.4.3 Protocol Limitations ........................................................................................................... 198 7.4.3 Implications and Future Research ...................................................................................... 199 7.4.4 Summary ............................................................................................................................ 200 CHAPTER VIII ........................................................................................................ 201 Study 5: A Second Uncontrolled Pilot Development Trial of an ACT-based Group Intervention for Post-DBT Patients with Poor Personality Functioning ....................... 201 8.1 Introduction ................................................................................................................. 201 8.2 Method ........................................................................................................................ 201 8.2.1 Design ................................................................................................................................ 201 8.2.2 Participants ......................................................................................................................... 201 8.2.3 Materials ............................................................................................................................. 204 8.2.4 Procedure ............................................................................................................................ 206 8.2.5 Analysis Plan ...................................................................................................................... 207 8.3 Results ......................................................................................................................... 207 8.3.1 Stage 1. Preliminary Analysis and Participant Characteristics .......................................... 207 8.3.2 Stage Two. Group Statistical Analyses and Effect Sizes ................................................... 209 8.3.3 Stage Three. Individual Participant RCIs ........................................................................... 212 8.3.4 Stage Four. Data Not Analysed Using the RCI Methodology ........................................... 217 8.4 Discussion ................................................................................................................... 221 8.4.1 Study Findings ................................................................................................................... 221 8.4.2 Methodological Limitations ............................................................................................... 227 8.4.3 Implications and Future Research ...................................................................................... 227 8.4.4 Summary ............................................................................................................................ 230 CHAPTER IX ........................................................................................................... 231 General Discussion .............................................................................................................. 231 9.1 Main Findings ............................................................................................................. 232 9.1.1 Analogue Research ............................................................................................................. 232 9.1.2 Applied research ................................................................................................................. 233 9.1.4 Main Strengths ................................................................................................................... 235 9.1.5 Main Limitations ................................................................................................................ 236 9.2 Implications and Suggestions for Future Research ..................................................... 237 9.2.1 CF, the CFQ, and the ACT Model ..................................................................................... 237 iv 9.2.3 Additional Mediators of Poor Personality Functioning ..................................................... 238 9.2.4 Behavioural Measures of Psychological Processes ........................................................... 239 9.2.5 Psychosocial Treatment of Poor Personality Functioning ................................................. 239 9.3 Concluding Remarks ................................................................................................... 240 APPENDICES .......................................................................................................... 242 Appendix A: Summary of principal methodological characteristics and results for all cognitive behavioural therapies RCTs for PD, organised by intervention type .................... 242 Appendix B: Cognitive Fusion Questionnaire ...................................................................... 261 Appendix C: Brief Demographics Questionnaire ................................................................. 262 Appendix D: Study 1 Research Ethics Committee Approval Letter ..................................... 263 Appendix E: Study 1 consent form, participant information sheet and debrief sheet .......... 264 Appendix F: Public access websites where Study 2 was hosted ........................................... 270 Appendix G: Study 2 demographic questionnaire/participant information/debrief sheet ..... 271 Appendix H: List of 48 self-referential adjectives used in Study 3 ...................................... 276 Appendix I: Study 3 Brief Demographics Questionnaire ..................................................... 277 Appendix J: Study 3 consent form, participant information sheet and debrief sheet ............ 278 Appendix K: Study 4: Details of protocol development ....................................................... 282 Appendix L: Studies 4 and 5 Research Ethics Committee Approval Letter ......................... 284 Appendix M: Studies 4 and 5 consent form, participant information sheet, and GP/CMHT information sheet ................................................................................................................... 285 Appendix N: Study 4: Details of treatment protocol ............................................................. 294 Appendix O: Life Activities Schedule .................................................................................. 297 REFERENCES ......................................................................................................... 300 LIST OF TABLES Chapter III Table 3.1 Measurement Methodologies and Data Output................................. 56 Chapter IV Table 4.1 Correlations Between the CFQ and Measures of Relevant Variables........................................................................................... 88 Table 4.2 Descriptive Data for CFQ Items....................................................... . 97 Table 4.3 Skew and Kurtosis Data for CFQ Items............................................ 97 Table 4.4 Fit Indices for CFA Comparing Four Factor Models for the CFQ.. . 100 Table 4.5 Cronbach’s α Coefficient for the CFQ, for Clinical and Non- Clinical Samples.............................................................................. . 101 Table 4.6 Normative data for the CFQ for clinical and non-clinical samples.. 102 Table 4.7 Correlations Between the CFQ and Measures of Psychopathology.. 103 Table 4.8 Correlations Between the CFQ and Measures of Relevant Variables........................................................................................... . 104 Chapter V Table 5.1 Demographic Information................................................................ . 116 Table 5.2 Skew and kurtosis data for all study variables................................. . 120 v Table 5.3 Means, Standard Deviation, and Internal Reliability Values for All Study Variables................................................................................. 121 Table 5.4 Inter-Correlations Between SIPP Subscales..................................... 122 Table 5.5 Bivariate Correlations Between Study Variables.............................. 122 Table 5.6 Tests of CF as a Mediator of Significant Associations between IVs and DV.............................................................................................. 125 Table 5.7 Fit Indices for Four Mediation Models............................................. 126 Chapter VI Table 6.1 Demographic Information................................................................ . 144 Table 6.2 Skew and Kurtosis Data for All Study Variables............................. . 148 Table 6.3 Means and Standard Deviations for All Study Variables................. . 148 Table 6.4 Paired Sample t Tests Comparing Positive and Negative View Time.................................................................................................. . 149 Table 6.5 Bivariate Correlations between CFQ Score and View Time........... . 150 Chapter VII Table 7.1 Demographics and Baseline Statistics.............................................. . 167 Table 7.2 PD Baseline Statistics....................................................................... . 168 Table 7.3 Weekly Session Topics.................................................................... . 176 Table 7.4 Means and Standard Deviations for All Study Measures................ . 182 Table 7.5 Friedman ANOVAs for Repeated Measures at Pre, Post, and Follow-Up......................................................................................... 183 Table 7.6 Reliable and Clinically Significant Individual Changes................... 185 Table 7.7 Changes in PD Diagnoses Based on 12-Month SCID-II Prevalence 189 Table 7.8 Participant Self-Harming Behaviour................................................. 190 Chapter VIII Table 8.1 Demographics and Baseline Statistics............................................... 203 Table 8.2 PD Baseline Statistics....................................................................... . 204 Table 8.3 Means and Standard Deviations for All Study Measures................ . 208 Table 8.4 Friedman ANOVAs for Repeated Measures at Pre, Post, and Follow-Up........................................................................................ . 210 Table 8.5 Effect Sizes....................................................................................... . 211 Table 8.6 Reliable and Clinically Significant Individual Changes................... 214 Table 8.7 Changes in PD Diagnoses Based on 12-Month SCID-II Prevalence 219 Table 8.8 Participant Self-Harming Behaviour................................................ . 220