Relationship Among Schizoid and Schizotypal Personality Traits and Social Support on PTSD ...

102 Pages·2013·0.7 MB·English

Eastern Michigan University
RELATIONSHIP AMONG SCHIZOID AND SCHIZOTYPAL PERSONALITY TRAITS AND
SOCIAL SUPPORT ON PTSD SYMPTOM SEVERITY

Wilfred McCloskey

Thesis

Submitted to the Department of Psychology

Eastern Michigan University

In partial fulfillment of the requirements

For the degree of

MASTER OF SCIENCE

PSYCHOLOGY

Thesis Committee:

Dean Lauterbach, PhD, Chair

Steven Huprich, PhD

John Knapp, PhD

February 15, 2013

Ypsilanti, MI
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Abstract
Posttraumatic stress disorder (PTSD) is a common disorder in the general population with
a lifetime prevalence of 7.8% (females 10.4%; males 5.0%; Kessler et al, 1995). PTSD can
become debilitating and can significantly affect an individual’s social and occupational
functioning. Consequently, it is essential to better understand the factors associated with
development and maintenance of PTSD. Research has documented the benefits of social support
in the prevention and treatment of PTSD. However, it is unclear whether other variables
moderate the effectiveness and desirability of social support. Currently, the empirical literature
examining the role of potential moderators of social support (e.g. specific personality
characteristics) is sparse. The goal of this study was to examine if two personality variables,
schizoid and schizotypal personality traits, moderate the relationship between social support and
PTSD. It was hypothesized that individuals who scored high on measures of these personality
traits will report less benefit from social support following a traumatic event than individuals
who scored low on measures of these traits. Participants (n = 386) were recruited from
undergraduate classes at a moderate sized Midwestern university via in-class presentations and
posted flyers. Results indicate that perceived social support is associated with lower PTSD
symptom severity. Further, both schizoid and schizotypal personality traits are associated with
elevated severity of PTSD, while schizotypal personality traits are associated with increased
trauma exposure. Finally, schizoid personality traits significantly moderate the relationship
between perceived social support and PTSD symptom severity.
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TABLE OF CONTENTS
Abstract…………………………………………………………………………………….ii
Table of Contents…………………………………………………………………………..iii
List of Tables………………………………………………………………………………vi
List of Figures……………………………………………………………………………...viii
Review of Related Literature…………………………………………………………………1
Introduction……………………………………………………………………….......1
Discussion of Posttraumatic Stress Disorder (PTSD) and Social Support…………...2
Predictors of and Risk Factors for PTSD…..…………………………………………7
Social Support……………………………..…………………………………………9
Relationship among PTSD, Social Networks, and Social Support……………….....10
Characteristics of Schizoid Personality Disorder……………………………………14
Characteristics of Schizotypal Personality Disorder………………………………...16
Personality Traits and Social Support…………………………………………….....17
Personality Traits and Trauma Exposure …………………………………………...18
Goals and Objectives of the Study…………………………………………………..19
Summary and Hypotheses………………………………………………….………..20
Research Design and Methods………………………………………………………………21
Participants……………………………………………………………………….....21
Research Design………………………………………………………………….....23
Measures….…………………………….…………………………………………...23
Procedures…………………………………………………………………………...30
Data Analyses …………………………………………………………………………….....33
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Results………………………………………………………………………………………37
Description of the Sample…………………………………………………………..37
Social Support and PTSD Symptom Severity……………………………………....38
Moderating Effects of Personality Traits ………………………………………......41
Relative Strength of Perceived and Received Social Support on PTSD Symptom
Severity……………………………………………………………………………...51
Correlation between Personality Traits and Trauma Exposure….………………………….51
Discussion…………………………………………………………………………………...51
Future Directions of Research………………………………………………………53
Limitations of the Present Study……………………………………………………56
Importance of Findings……………………………………………………………..58
References…………………………………………………………………………………..60
Appendix A: Recruitment Script …………………………………………………………...72
Appendix B: Schizotypal Personality Questionnaire (SPQ) ………………………….……73
Appendix C: Inventory of Socially Supportive Behaviors (ISSB) …………………………75
Appendix D: The Multidimensional Scale of Perceived Social Support (MSPSS)…………76
Appendix E: Purdue PTSD Scale – Revised (PPTSD-R)…………………………………...77
Appendix F: Posttraumatic Stress Disorder Checklist Revised – Civilian (PCL-R)………..78
Appendix G: Personality Disorders Questionnaire – Version 4 (PDQ-4+)…………………80
Appendix H: Traumatic Events Questionnaire – Revised (TEQ- R)……………………….83
Appendix I: Study Description………….…………………………………………………..90
Appendix J: Informed Consent Document………………………………………………….91
Appendix K: Demographics Questionnaire………………………………………………...92
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Appendix L: Debriefing Document………………………………………………………...93
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List of Tables
Table 1. DSM-IV-TR Diagnostic Criteria for Posttraumatic Stress Disorder (PTSD)………3
Table 2. Proposed DSM-5 Diagnostic Criteria for Posttraumatic Stress Disorder (PTSD)….4
Table 3. Participant Demographics…………………………………………………………..38
Table 4a. Relationship between Perceived Social Support and Posttraumatic Stress Disorder
(PPTSD-R)………………………………………………………………………..39
Table 4b. Relationship between Perceived Social Support and Posttraumatic Stress Disorder
(PCL-R)…………………………………………………………………………..39
Table 4c. Relationship between Perceived Social Support and Posttraumatic Stress Disorder
(DSM-5)………………………………………………………………………….40
Table 4d. Relationship between Received Social Support and Posttraumatic Stress Disorder
(PPTSD-R)……………………………………………………………………….40
Table 4e. Relationship between Received Social Support and Posttraumatic Stress Disorder
(PCL-R)………………………………………………………………………….40
Table 4f. Relationship between Received Social Support and Posttraumatic Stress Disorder
(DSM-5) …………………………………………………………………………40
Table 5a. Relationship between Schizoid Personality Traits, Perceived Social Support, and
PTSD (PPTSD-R)……………………………………………………………….42
Table 5b. Relationship between Schizoid Personality Traits, Perceived Social Support, and PTSD
(PCL-R) ………………………………………………………………………….42
Table 5c. Relationship between Schizoid Personality Traits, Perceived Social Support, and PTSD
(DSM-5) ………………………………………………………………………….43
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Table 5d. Relationship between Schizoid Personality Traits, Received Social Support, and PTSD
(PPTSD-R) ………………………………………………………………………43
Table 5e. Relationship between Schizoid Personality Traits, Received Social Support, and PTSD
(PCL-R) ………………………………………………………………………….44
Table 5f. Relationship between Schizoid Personality Traits, Received Social Support, and PTSD
(DSM-5) ………………………………………………………………………….44
Table 6a. Relationship between Schizotypal Personality Traits, Perceived Social Support, and
PTSD (PPTSD-R) ………………………………………………………………..48
Table 6b. Relationship between Schizotypal Personality Traits, Perceived Social Support, and
PTSD (PCL-R)……………………………………………………………………48
Table 6c. Relationship between Schizotypal Personality Traits, Perceived Social Support, and
PTSD (DSM-5)……………………………………………………………………49
Table 6d. Relationship between Schizotypal Personality Traits, Received Social Support, and
PTSD (PPTSD-R)…………………………………………………………………49
Table 6e. Relationship between Schizotypal Personality Traits, Received Social Support, and
PTSD (PCL-R)……………………………………………………………………50
Table 6f. Relationship between Schizotypal Personality Traits, Received Social Support, and
PTSD (DSM-5)…………………………………………………………………...50
Table 7. Correlation between Personality Traits and Trauma Exposure…………………….51
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List of Figures
Figure 1. Moderating Effect of Schizoid Personality Traits on the Relationship between
Perceived Social Support and PTSD (PCL-R)……………………………………46
Review of Related Literature
Introduction
A considerable body of research has examined the benefits of social support in the
reduction of posttraumatic stress disorder (PTSD) symptomology. The consensus is that lower
levels of social support are associated with more severe symptoms of PTSD. This finding has
been observed in a broad array of samples including police officers in New Zealand (Stephens,
Long, & Miller, 1997) and breast cancer survivors in the United States (Andrykowsky &
Cordova, 1998). The results of a recent meta-analysis support the association between social
support and PTSD symptomology as well (Ozer, Best, Lipsey, & Weiss, 2008). Ozer et al.
(2008), using data from 11 studies, found a small to moderate negative correlation between
perceived social support following a traumatic event and PTSD symptomology. This negative
relationship suggests PTSD symptoms are more severe when individuals feel as though social
support is unavailable to them.
The relationship between support and PTSD may also be bidirectional. That is, persons
with more severe symptoms of PTSD symptomology may elicit less social support than a non-
PTSD population. There is a strong negative correlation between PTSD symptoms and the
amount, and quality, of social support later in life due to the increase in interpersonal difficulties
associated with the symptoms of PTSD (King, Taft, King, Hammond, & Stone, 2006).
Despite the extensive body of research outlining the benefits of social support following
trauma, this support may not be universally helpful and may be detrimental to certain
individuals. Recent research suggests that the amount of benefit one may derive from social
support may be a function of one’s personal predisposition to either interdependence or
independence. Individuals who value social interdependence tend to derive more satisfaction