Predictors and Mediators of Anger and Aggression in Schizophrenia Spectrum Disorders A thesis ...

171 Pages·2015·12.47 MB·English

Predictors and Mediators of Anger and Aggression in Schizophrenia Spectrum
Disorders

A thesis submitted to the University of Manchester for the degree of Clinical
Psychology Doctorate in the Faculty of Medical and Human Sciences

2015

Hannah Darrell-Berry

SCHOOL OF PSYCHOLOGICAL SCIENCES
Section of Clinical and Health Psychology
1
Table of contents

List of appendices……………………………….………………………….…………………………………………... 4
List of tables and figures………………………….………………………….………………………………………..5
Thesis abstract………………………….………………………….………………………….…………………………. 6
Declaration, copyright and ownership………………………….……………………………………………… 7
Acknowledgements………………………….………………………….……………………………………………… 8

Paper one: systematic review
Title page……….………………………….……….………………………….……….………………….…. 9
Abstract ……….………………………….……….………………………….……….………………….…. 10
1. Introduction ……….………………………….……….………………………….……….…….……11
2. Method ……….………………………….……….………………………….……….…………….…. 12
2.1 Eligibility criteria ……….………………………….……….…………………………. .……12
2.2 Search strategy ……….………………………….……….…………………………..…….….12
2.3 Study selection and data extraction ……….………………………….……….….…. 13
2.4 Quality assessment ……….………………………….……….………………………….…. 15
3. Results ……….………………………….……….……………………………………………………….. 15
3.1 Overview of studies ……….………………………….……….……………………………. 15
3.2 Study quality ……….………………………….……….………………………………………. 16
3.3 Relationship between paranoia and aggression in psychosis ……….…..… 22
3.3.1 Group comparison studies ……….……………………………………………... 22
3.3.2 Correlational studies ……….……………………………………………………… 23
4. Discussion ……….………………………….……….………………………….……….……………… 25
4.1 Summary of findings ……….………………………….……….…………………..………. 25
4.2 Previous literature ……….………………………….……….………………………..……. 26
4.3 Limitations ……….………………………….……….…………………………………………. 27
4.4 Clinical implications ……….………………………….……….………………………...…. 28
4.5 Future directions ……….………………………….……….…………………………….….. 28
5. References ……….………………………….……….………………………….……….…..………..… 30

Paper two: empirical research
Title page ……….………………………….……….………………………….……….……………………35
Abstract ……….………………………….……….………………………….……….………………….…. 36
1. Introduction ……….………………………….……….………………………….…………………… 37
2. Method ……….………………………….……….………………………………………………………. 40
2.1 Sample ………….………………….………………….………………….……………….. 40
2.1.1 Inclusion criteria ……….…………………………………………...…. 41
2.1.2 Ultra-high risk of psychosis sample ……….…………………… 41
1
2.1.3 First-episode psychosis sample ……….…………………..….… 41
2.1.4 Established psychosis sample ……….…………………….….…. 41
2.1.5. Non-clinical sample ……….………………………………….….….. 41
2.1.6 Exclusion criteria ……….…………………………………………….. 41
2.2 Measures ……….………………………….……….……………………………………. 42
2.2.1 Anger ……….………………………….……….……………………….…. 42
2.2.2 Attachment ……….………………………….……….……………….… 42
2.2.3 Paranoia ……….………………………….……….……………………… 42
2.2.4 Social cognition ……….………………………….……….………….…43
2.2.5. Confounding variables ……….…………………………………….. 43
2.2.6 Psychopathology ……….………………………….……….…….…… 44
2.3 Procedure ……….………………………….……….………………………………..…. 42
2.4 Statistical analysis ……….………………………….……….………………………. 44
3. Results ……….………………………….……….………………………….……….………………..… 45
3.1 Demographic characteristics ……….………………………….……….…..…… 45
3.2 Group comparison and covariate analyses ……….…………………..……. 46
3.3 Predictors of anger hypothesis ……….…………………………………………. 49
3.4 Social cognition as a mediator ……….………………………………………….. 52
3.5 Paranoia as a mediator ……….………………………….……….……………...… 52
4. Discussion ……….………………………….……….………………………….……….…….….……. 53
5. References ……….………………………….……….………………………….…………..….……….57

Paper three: Critical reflection
Title page ……….………………………….……….………………………….……….……………….… 64
1. Introduction ……….………………………….……….………………………….……….…….… 65
2. Paper one: Systematic literature review ……….………………………….…..………. 65
2.1 Topic selection ……….………………………….……….…………………………….65
2.2 Search terms ……….………………………….……….………………………………. 67
2.3 Inclusion and exclusion criteria ……….………………………….……………. 67
2.4 Contacting authors ……….………………………….……….………………………. 69
2.5 The question of meta-analysis ……….………………………….……….……… 69
2.6 Quality assessment ……….………………………….……….……………………… 69
2.7 Clinical implications ……….………………………….……….………………….…. 70
2.8 Future directions ……….………………………….……….…………………………. 71
3. Paper two: empirical research ……….………………………….……….…………….….…… 72
3.1 Contribution to the project ………………………………………………….…….. 72
3.2 Choosing the mediators ……….……………………….………………………..…. 74
3.3 Measures ……….………………………….……….………………………………….…. 75
3.4 Confounding variables ……….………………………………………………..……. 78
3.5 Data analysis ……….………………………….……….………………….……………. 79
2
3.6 Other limitations ……….………………………….……….……………..……………80
3.7 Clinical implications ……….………………………….……….………………..…… 81
3.8 Future directions ……….………………………….……….…………………………. 81
4. Personal reflections ……….………………………….……….……………………………….…... 82
5. References ……….………………………….……….……………………………………………...…. 85

Total thesis word count: 16,814 (excluding tables, figures and references)
3
List of appendices

Appendix A: Instructions to authors: Schizophrenia Research ……….………………………….…. 92
Appendix B: Instructions to authors: Journal of Psychiatric Research ……….…………………. 105
Appendix C: NHS ethical approval ……….………………………………………………………………….…. 117
Appendix D: Participant information sheets ……….…………………………………………...…………. 123
Appendix E: Consent forms ……….………………………….……….…………………………………….……. 133
Appendix F: Demographics form ……….………………………….……….……………………………..…… 138
Appendix G: Psychosis Attachment Measure ……….……………………………………………….……. 140
Appendix H: Green Paranoid Thoughts Scale ……….…………………………………………….………. 144
Appendix I: Hinting task ……….………………………………………………………………………………..…. 147
Appendix J: Ambiguous Intentions Hostility Questionnaire ……….…………..……………………. 159
Appendix K Calgary Depression Scale ……….………….…………………………………………………….. 167
Appendix L: Barratt Impulsivity Scale ……….……………………………………………………….………. 169

4
List of tables and figures

Paper one: systematic review
Figure 1: Flow diagram of systematic search ……….………………………………….………. 14
Table 1: Summary of included studies ……….………………………….……….…………..…… 18
Table 2: Quality ratings for included studies ……….……………………………………….…. 21

Paper two: empirical research
Table 1: Demographic characteristics of the sample ……….……………………….………. 46
Table 2: Measure mean scores and summary statistics ……….……………………...……. 48
Table 3: Pearson’s correlations between all variables ……….………………………..……. 50
Table 4: Summary of regression analysis ……….……………………………………………..…. 51
Figure 1: Mediation model of hostile attribution bias, attachment avoidance and
trait anger ……….………………………….……….………………………….……….…………………….. 52
Figure 2: Mediation model of paranoia, attachment avoidance and trait anger ..… 53

Paper three: critical evaluation
Figure 1: Illustration of a mediation model ………………………………………………………79

5
Thesis Abstract

The aim of this thesis was to explore the relationship between anger and aggression, insecure
attachment, paranoia and social cognition in psychosis. It is presented as three separate papers: 1) a
systematic review examining the relationship between paranoia and aggression in schizophrenia
spectrum disorders, 2) an empirical study investigating predictors and mediators of trait anger across
the psychosis continuum: the role of insecure attachment, paranoia and social cognition and 3) a
critical reflection of the research process.

Paper one provides a systematic review of the relationship between paranoia and aggression in
schizophrenia spectrum disorders. A comprehensive search of the published literature identified
fifteen eligible studies. The quality of the included articles is critically appraised during the synthesis
of the findings. Methodological limitations, clinical implications and recommendations for future
research are considered.

Paper two provides an examination of predictors and mediators of trait anger across the psychosis
continuum, considering the role of insecure attachment, paranoia and social cognition. Tests of theory
of mind and measures of attachment, hostile attribution bias, paranoia and anger were administered to
174 participants (14 ultra-high risk of psychosis, 20 first-episode psychosis, 20 established psychosis
and 120 non-clinical). Multiple regression analysis found attachment avoidance, paranoia and hostile
attribution bias were significantly related to trait anger. Mediation analysis revealed paranoia
mediated the relationship between attachment avoidance and trait anger. The results are discussed
with consideration to previous research and limitations of the study. Clinical implications and
recommendations for future research are also offered.

Paper three provides a critical reflection of papers one and two, with reference to their design,
implementation and interpretation. Personal reflections of the research process as a whole are also
provided.

6
Declaration
No portion of the work referred to in this thesis has been submitted in support of an application for
another degree or qualification of this or any other university or other institute of learning.

Copyright and Ownership
The author of this thesis (including any appendices and/or schedules to this thesis) owns certain
copyright or related rights in it (the “Copyright”) and s/he has given The University of Manchester
certain rights to use such Copyright, including for administrative purposes.
Copies of this thesis, either in full or in extracts and whether in hard or electronic copy, may be made
only in accordance with the Copyright, Designs and Patents Act 1988 (as amended) and regulations
issued under it or, where appropriate, in accordance with licensing agreements which the University
has from time to time. This page must form part of any such copies made.
The ownership of certain Copyright, patents, designs, trade marks and other intellectual property (the
“Intellectual Property”) and any reproductions of copyright works in the thesis, for example graphs
and tables (“Reproductions”), which may be described in this thesis, may not be owned by the author
and may be owned by third parties. Such Intellectual Property and Reproductions cannot and must not
be made available for use without the prior written permission of the owner(s) of the relevant
Intellectual Property and/or Reproductions.
Further information on the conditions under which disclosure, publication and commercialisation of
this thesis, the Copyright and any Intellectual Property and/or Reproductions described in it may take
place is available in the University IP Policy (see
http://documents.manchester.ac.uk/DocuInfo.aspx?DocID=487), in any relevant Thesis restriction
declarations deposited in the University Library, The University Library’s regulations (see
http://www.manchester.ac.uk/library/aboutus/regulations) and in The University’s policy on
Presentation of Theses

7
Acknowledgements
I would like to extend my gratitude to the individuals who participated in this research and the
services and clinicians who supported it.

My sincere thanks go to Katherine and Sandra, my supervisors. I am truly grateful for the guidance
and encouragement you have provided throughout. I consider myself fortunate to have had the
opportunity to learn from you– thank you.

Last but not least, to my wonderful family. Thank you to Mam and Chris, for your unconditional love
and support. Thank you to Gramma, for your faith in me and in what I can achieve. Thank you to
Nikki, for your patience, encouragement, love and cups of tea.

8
Paper 1: The Relationship between Paranoia and Aggression in Schizophrenia Spectrum
Disorders

The following paper has been prepared for submission to ‘Schizophrenia Research’. The guidelines for
authors are presented in appendix A.

Word count: 4, 765 (excluding tables, figures and references)
9