Faculty of Social and Behavioural Sciences
‘The influence of gender, refugee status, and symptom severity in complex PTSD
treatment’
MASTER THESIS
2015 – 2016
Michael J. Lans, BSc
Department: Clinical Psychology
Research mentor: H. Uhr-Daal & T.M. Mooren
University mentor: J.W. Knipscheer
In commission of Centrum ’45/Arq & Utrecht University
Abstract
Research on prognostic factors concerning effectiveness of mental health interventions, is
limited; it is most difficult to say who will benefit why of which intervention. Nonetheless,
there is evidence that specific variables have some predictive value regarding the
effectiveness of PTSD related treatment; the most important factors are gender, refugee status
and symptom severity. In this study treatment response (i.e. PTSD symptom reduction) was
analysed using the Harvard Trauma Questionnaire among 34 participants before and after
treatment. The main results suggest that trauma focussed treatment may have a role in
reducing symptom clusters of PTSD but gender and refugee status do not influence treatment
response. The conclusion might indicate that men, females, refugees, and natives may all
profit equally from trauma-focused treatment.
1
Preface
The thesis “The influence of gender, refugee status, and symptom severity in complex PTSD
treatment” lies before you and is the end result of internship with Centrum ‘45/Arq. It has
been written to accomplish the graduation requirements of the master Clinical Health
Psychology at the University Utrecht. The research for this thesis has been conducted between
2014 and 2015.
This research can be seen as a pilot study for a different research for which I undertook the
internship with centrum ’45. Together with my supervisors of Centrum ’45, Hanna Urh-Daal
and Trudy Mooren and my mentor of the University, Jeroen Knipscheer different research
questions were formulated. It has been a process, which was at times difficult and daring, not
only professionally but also personally.
I would like to thank all of my mentors for their patients, guidance, and critics. I know I can
be a handful, but you all have been there for me when I was lost and helped me to finally
finish this process. Besides my mentors I would like to name my friends and family. They
have tried to keep me motivated, whenever I was lost.
I hope you enjoy your reading,
Michael Jeffrey Lans
Utrecht, July 18, 2016.
2
Index
Abstract ................................................................................................................................................1
Preface ..................................................................................................................................................2
Introduction .......................................................................................................................................4
Complex post-traumatic stress disorder ............................................................................................ 4
Content and working mechanisms of Trauma-Focussed Therapy ............................................ 4
Prognostic factors ....................................................................................................................................... 5
Research ......................................................................................................................................................... 6
Method..................................................................................................................................................7
Participants ................................................................................................................................................... 7
Instruments ................................................................................................................................................... 9
Analyses .......................................................................................................................................................... 9
Results ............................................................................................................................................... 10
Discussion ........................................................................................................................................ 11
References ........................................................................................................................................ 14
3
Introduction
Complex post-traumatic stress disorder
Post-traumatic stress disorder (PTSD) is the standard axiom to cluster psychological
phenomena that ascend as a reaction to a traumatic experience (Vermetten, Kleber, & van der
Hart, 2012; Yehuda, 2002). The psychological phenomena of PTSD are categorized in the
DSM IV, using three clusters (American Psychiatric Association, 2013): Intrusions (the
traumatic event is persistently re-experienced in one or more ways, such as nightmares and
intrusive recollections of the event; the re-experience triggers psychological distress and
physical reactions); Avoidance (stimuli associated with the trauma are persistently and
actively avoided, and aspects of the event are unable to recall); and Hyperarousal (persistent
symptoms of increased arousal, such as irritability, difficulty falling or staying asleep, or
hypervigilance). The clusters of PTSD provide an adequate and workable description,
however some trauma survivors have a multitude of ancillary problems, which may be
covered by a different term, namely complex PTSD (American Psychiatric Association, 2013;
Taylor, Asmundson & Carleton, 2006; Vermetten, Kleber, & van der Hart, 2012).
Complex PTSD is characterized by high comorbidity on both DSM-IV clinical disorders
(Axis I) and personality disorders (Axis II), with symptom domains of addiction, negative
self-concept, and interpersonal disturbances (Dorrepaal et al., 2014). Empirical studies as well
as neurobiological findings support the distinction between the effects of singular trauma
against multiple or chronic traumata. Studies agree that multiple or chronic traumata can
cause complex PTSD (Kleber & Mooren, 2014). Nonetheless complex PTSD lacks of a wellaccepted definition. This results in inaudibility, which has effect on all trauma-focussed
therapy (Foa, Keane & Friendman, 2000; ter Heide, Kleber & Mooren, 2014).
Content and working mechanisms of Trauma-Focussed Therapy
The Dutch guideline for treating PTSD dictates the use of evidence based trauma-focused
therapy (TFT) as first choice treatment. The evidence based TFT’s that are recommended are
trauma focused cognitive behaviour therapy (TF-CBT) and eye movement desensitisation and
reprocessing (EMDR). Both TF-CBT and EMDR have been proven effective over other
treatments
(http://www.ggzrichtlijnen.nl/index.php?pagina=/richtlijn/item/pagina.php&id=431&richtlijn
_id=35; Casack, et al., 2016; Jongh, et al., 2016). In addition, narrative exposure therapy
(NET) is a relatively new treatment with good effectiveness rates (Casack, et al., 2016). The
intervention is not classified as first choice yet, but has been implemented into the range of
4
treatments. This might indicate that it may gain strong evidence over time, like TF-CBT and
EMDR (Neuner, Schauer & Elbert, 2014).
TF-CBT is effective in reducing the severity of PTSD symptoms as other psychological
states that may occur, such as depression (Foa, Keane & Friendman, 2000). The therapy
includes imaginal exposure and other techniques in order to manage the overwhelming
feelings PTSD can bring. Imaginal exposure confronts the patient to stimuli related to the
traumatic experience.
Another intervention focuses on the autobiographical memory, which are recollections of
events of the past. Traumatic events may cause a disturbance within the patterns. The
disturbance has effect on emotional memories, which may cause intrusions and ruminations.
The intervention of memory processing targets the maladaptive memory processes and tries to
reverse these. Also the negative cognitions and assumptions one might have developed
regarding the traumatic event will be questioned and if necessary replaced by more realistic
beliefs (Foa, Keane & Friendman, 2000).
EMDR reduces the image vividness and emotional intensity of an aversive memory by
recollection. The therapy itself consists of a dual-task; making bilateral eye movements,
during the recall of traumatic memory (Shapiro, 1989). The mechanism of EMDR lies with
the limited resources of the working memory, which is taxed during the dual-task. This leads
to impairment during the retrieval of the image with its accompanied details and emotions,
which results in an immediate decreased image vividness and emotional intensity before it is
return to long-term store (Shapiro, 1989; Leer, Engelhard & van den Hout, 2014).
NET is a form of exposure therapy for clients who experienced multiple traumas
(Schauer, Neuner, & Elbert, 2011). To explain the mechanism behind NET we have to focus
on the effect of experiencing cumulative multiple traumas. These emotional memories are tied
in a network with sensory, cognitive, emotional, and physiological elements. This network is
broadened into a fear network, which can be triggered by exposure to any of the cues
contained within the network from any of the traumatic events a person has experienced
(Schauer, Neuner, & Elbert, 2011).
Prognostic factors
Enhancing knowledge of prognostic factors, which affect treatment outcome, is important.
This knowledge can be helpful in adequately indicating treatment. However, research on
prognostic factors is limited, and previous research show divergent results. Therefore it is
difficult to say who will benefit of which intervention (Morina, Wicherts, Lobbrecht, &
Priebe, 2014). Nonetheless, evidence exists that specifies variables, which have some
5
predictive value regarding the effectiveness of PTSD related treatment; the most empirically
supported factors are gender, refugee status and symptom severity.
Research suggests that women have a greater risk of developing PTSD following
exposure to a traumatic event than men (Wade et al., 2016; Hourani, Williams, Bray, Wilk, &
Hoge, 2016). Regarding gender as a prognostic factor, a recent meta-analysis reports both
men and women have equal positive treatment outcome with TFT (Wade et al., 2016).
However, Tarrier, Sommerfield, Pilgrim, and Faragher (2000) report a better treatment
outcome for females, suggesting females are more expressive about their emotional
tribulations and participate more during treatment. Although the meta-analysis provides
stronger evidence, there may still be some doubt and discussion regarding the outcome in the
clinical practise (Van Minnen, Arntz, & Keijsers, 2002).
Another prognostic factor concerns the status of having a refugee background or a native
background. Refugees are at higher risk to develop PTSD than non-refugees, due to the type
and number of their experienced trauma and the on going experienced stress afterwards.
Research regarding treatment responds is conflicted. Ter Heide and Smid (2015) suggest that
refugees have lower treatment responses than non-refugees, which they explain by a threefold of factors on which both patient and therapist have no control. Therefore they suggest a
realistic expectation of trauma-focused therapy. In contrast, Lambert and Alhassoon (2015)
performed a meta-analysis which showed no significant difference in treatment responses, the
authors suggest that the stated trauma paradigm in western society can be effectivly projected
on refugees and other non-western populations.
The severity of PTSD symptoms is also a prognostic factor for treatment outcome that
gives mixed results. A recent meta-analysis (Haagen, Smid, Knipscheer, & Kleber, 2015)
reported a relationship between a higher number of PTSD symptoms at pre-treatment and
poor treatment outcome, whilst a systematic review, regarding refugee subjects (Palic &
Elklit, 2011) found that more onset severity is related to better treatment outcome. In the latter
study, patients with severe symptoms showed more fear activation during exposure sessions,
and therefore better outcome. In other meta-analyses, no relationship between pre-treatment
severity of symptoms and treatment outcome was reported (Tarrier et al., 2000; Van Minnen,
Arntz, & Keijsers, 2002).
Research
The present study will add to the knowledge about prognostic factors, which is important for
theoretical development of the trauma and PTSD field. In addition, the clinical practise can be
improved with this knowledge in order to help people who suffer from complex PTSD more
6
efficiently. Three prognostic factors will be accounted for: the severity of PTSD symptoms,
gender, and refugee status.
The possible prognostic factors are first analysed separately to explore if there is a
difference in treatment response, starting with the severity of PTSD symptoms. Research
suggests a better treatment effect with severe symptoms at the beginning of the treatment, as
there is more fear activation during exposure sessions (Van Minnen, Arntz, & Keijsers, 2002).
As the instituion where this research will be conducted treats patients with complex PTSD,
the severity of the symptonology will be high and therefore the hypothesis is that a decrease
will occur on all three symptoms clusters of PTSD after TFT.
In addition, gender will be analysed as a prognostic factor of treatment response in
trauma-focussed therapy. Research has found a better treatment outcome in females (Tarrier
et al., 2000) though other studies, with higher levels of evidence, couldn’t confirm this (Wade
et al., 2016; Van Minnen, Arntz, & Keijsers, 2002). Thus, the expectation is to find equal
treatment responses between men and females.
The last prognostic factor analysed is being a refugee. A meta-analysis showed no
difference in treatment responses regarding refugee status (Lambert & Alhassoon, 2015).
However a single study showed that refugees have a lower treatment response than nonrefugees on TFT (ter Heide & Smid, 2015). Due the cause of this contradiction the
expectation is to find better treatment outcome for non-refugees after TFT.
After we have looked into these possible prognostic factors separately, this study will
explore in a multivariate way which factor explains most variance in treatment outcome of
TFT.
Method
This study was conducted at Foundation Centrum ’45, which is a highly specialised Dutch
centre for diagnostics and treatment of psycho-trauma. The centre receives national referrals
of patients considered too complex to be treated by local mental health care. Data collected in
the period 2012 until 2015, were used, in which participants received either EMDR or NET.
Data were collected during the process of routine outcome monitoring (ROM), a method to
collect information about the wellbeing of patients on a regular base. The ROM included the
Harvard Trauma Questionnaire (HTQ) to follow the effect of treatment on the symptoms of
PTSD.
Participants
Between 2012 and 2015, 658 patients started and finished either EMDR or NET. To be
7
included in this study, the first ROM assessment had to be taken six month before or one
month after the first trauma focussed session. The second inclusion condition concerned the
second ROM assessment, which had to be taken two weeks or seven months after the last
trauma focussed session. Due to this timeframe, only 54 participants could be included. In
addition, only participants who had filled out the Harvard Trauma Questionnaire (HTQ) at
both assessments were used. This resulted in sample of 21 participants who followed the
EMDR protocol and 13 participants who followed the NET protocol, which resulted in a total
of 34 participants.
Table 1 gives an overflow of the demographic statistics of all participants, which
includes: trauma-focused treatment, gender and treatment group. Treatment group is
furthermore specified with place of birth. Both gender (t(32) =-.43 , p =.66) and treatment
group (t(31.8) =-1.57 , p =.12) did not differ significantly on PTSD during baseline using a
independent t-test.
Table 1
Demographic statistics of gender and treatment group
Frequency
Percentage
Age (M/SD)
Trauma-focused treatment
34
100
45(10,9)
EMDR
21
62
44(10,7)
NET
13
38
46(11,5)
Male
23
67
46(7.8)
Female
11
33
42(15.6)
13
38
41(9.9)
Azerbaijan
1
8
Bosnia and Herzegovina
2
15
Iraq
1
8
Iran
2
15
Yugoslavia
2
15
Congo
1
8
Russia
1
8
Sierra Leone
1
8
Somalia
1
8
Gender
Treatment group
Refugees
8
Turkey
1
8
Non-refugees
21
62
Netherlands
19
95
Netherlands East Indies
2
5
47(11.1)
Instruments
The Harvard Trauma Questionnaire (HTQ; Mollica et al., 1992) was used to assess PTSD
symptoms. The HTQ is a self-report scale and consists out of 17 items format, with three
subscales assessing the three separate symptom clusters intrusion, arousal, and avoidance as
specified by the DSM-IV rated on a four-point Likert type scale (1 = not al all, 4 = all the
time). An example would be “Sudden emotional or physical reaction when reminded of the
most hurtful event”. A cut-off score of 2.5 is in place, which means that by a score of ≥2.5
PTSD is suggested. The reliability of the total scale in the current study was high (Cronbach’s
= 0.92). The original HTQ was especially designed for studying refugees, however the Dutch
version of the HTQ has been used in a wide range of trauma populations with reports of good
reliability and validity (Kleijn, Hovens & Rodenburg, 2001).
Analyses
The analyses were performed with ‘The Statistical Package of Social Sciences’ (SPSS) version
20.0 (IBM Corp, 2011). First, mean differences on HTQ total scores between the two
measurements (before and after treatment) were analysed. Next, the three hypotheses were tested.
In order to analyse the influence of severity of cluster symptoms, a repeated measures analysis of
variance (ANOVA) is used; with dependent variable PTSD (HTQ, total score) and independent
variables intrusion (HTQ-IN), hyperarousal (HTQ-HYP) and avoidance (HTQ-AV). All the
assumptions were made. An alpha of .05 was set in place. In addition, two independent samples ttest are used. A differential score was made for the HTQ (before – after). The first independent
samples t-test is performed with an independent variable “gender” and a dependent variable
“PTSD”. The second independent samples t-test was executed with an independent variable
“refugee status” and a dependent variable “PTSD”. All the assumptions were made. An alpha of
.05 was set in place.
To explore which of the prognostic factors explained the most in variance, a multiple
regression was performed, with dependent variable “PTSD” and independent variables “gender”,
“refugee status”, and scores for intrusion, hyperarousal, and avoidance. An alpha of .05 was set in
place.
9
Results
The mean score on the HTQ before treatment was 2.93(SD =.56). There were six participants
who scored below the cut-off of 2.5. After treatment, the mean score had been reduced to 2.58
(t(33) =2.87 , p =.01), still slightly above cut-off level. Table 2 shows the means on the HTQ
in total and on the cluster symptoms before and after treatment.
Table 2
Descriptions of means and standard deviations on the HTQ and its subscales before and
after treatment
Before treatment
After treatment
HTQ
2.93(SD =.56)
2.58(SD =.81)
Intrusion
3.01(SD =.74)
2.70(SD =.96)
Avoidance
2.74(SD =.63)
2.43(SD =.79)
Hyperarousal
3.15(SD =.55)
2.69(SD =.88)
The cluster symptoms as prognostic factor
The repeated measure ANOVA showed a statistically significant difference at p < .05 level on
all three clusters (for intrusion: F(1, 33) = 4.74, p = .037, avoidance: F(1, 33) = 5.08, p =
.031, and hyperarousal: F(1, 33) = 12.23, p = .001.), indicating that overtime TFT has a
positive influence on the HTQ considering all clusters.
Gender as prognostic factor
An independent-samples t-test to compare PTSD total scores before and after treatment for
men (M=.49, SD=.75) and women (M=.06, SD=.56) showed no significant difference on
treatment response; t(32)= 1.71, p = .097.
Being a refugee or a non-refugee as prognostic factor
An independent-samples t-test to compare PTSD total scores before and after treatment for
refugees (M=.42, SD=.73) and non-refugees (M=.31, SD=.72) yielded no significant
differences on treatment response; t(32)= -0.43, p = .674.
Variance in treatment outcome
Correlation and multiple regression analyses were used to explore the relationship between
10
the predictor factors and treatment outcome. Table 3 gives a summary of correlations, due the
assumption of multicollinearity predictor variables: intrusion, hyperarousal, and avoidance
were excluded from the multiple regression analyses. The assumptions for the new model
were all made.
Using the enter method it was found that gender (1 = male, 2 = female, M = 1.32, SD
=.47), refugee status (1 = non-refugee, 2 = refugee, M = 1.38, SD=.49) did not explain a
significant amount of the variance in treatment responds (F(2, 31) = 1.625, ns , R2 = .095,
R2Adjusted = .036).
Table 3
Summary of correlations
Gender
Gender
Refugee Status
Intrusion
Hyperarousal
Avoidance
1
Refugee status
.103
1
Intrusion
-.337
.010
1
Hyperarousal
-.303
.009
.670**
1
Avoidance
-.178
.151
.711**
.748**
1
*p < .05, **p < .01, ***p < .001
Discussion
This study has used pre-treatment severity of PTSD symptoms, gender, and refugee status of
34 patients to find prognostic factors influencing treatment effectiveness. The sample has
been acquired out the database of Foundation Centrum ’45, PTSD levels are measured with
the HTQ, before and after trauma-focused treatment. Each prognostic factor is analysed
separately, before a multiple regression analysis tries to explain the variance of each factor.
The overall results suggest that severity of PTSD symptoms, gender and refugee status have
NO effect on PTSD change after treatment. This might indicate that men, females, refugees,
and natives may all profit equally from trauma-focused treatment.
The outcome of treatment seems difficult to predict, while using the factors researched
within this study. The suggestion can be made that gender and refugee-status indeed might
not influence treatment outcome as is in line with other studies (Lambert & Alhassoon, 2015:
Wade et al., 2016). Otherwise, gender and refugee status might have been interferenced by
another factor, suggestions can be made such as duration of treatment or the therapists gender,
which invites further research necessary to explore this further.
11
This research does not find difference in treatment responds between men and females or
refugees and natives. The results shows the same decreasing effect of trauma-focused
treatment on PTSD, which may suggest that trauma-focused treatment has a positive effect on
men, females, refugees, and natives. However we have to mention that this positive effect on
symptoms does not indicated no or fewer symptoms, as the overall mean of the HTQ stays
just above the cut-off point. Caution is needed interpreting the outcome, as trauma-focused
treatment is not specified, not only as two trauma-focused treatments are accounted for during
this study, but also because we do not know if both or one of the other might explain the
found effect. This could likewise have been of influence on the outcome regarding gender,
where Tarrier, Sommerfield, Pilgrim, and Faragher (2000) reports a better treatment outcome
for females suggesting they where more expressive during treatment. This reasoning might
lead to the idea that females venture better with NET, while men, whom find it difficult to
express their psychological difficulties, might strive better with EMDR. Our research
however suggests that both men and female may equally profit from trauma-focused
treatment. Concerning refugee status the treatment difficulties, such as language, on-going
stress and uncertainty, should not be denied (ter Heide & Smid, 2015). This research does not
accounts for the duration and progress of treatment, while ter Heide and Smid, (2015) argued
that refugees need more sessions, have a high level of drop-out and miss more sessions
overall than natives. Our research suggests a positive effect of trauma-focused treatment on
PTSD disregarding refugee status, however duration of treatment is not accounted for. Due
this positive effect we also might suggest that all the efforts to make therapy more culturally
sensitive for refugees are unnecessary.
The current study has some strengths and limitations that need to be addressed when
interpreting the results. The strength of this study is that all the statistic assumptions regarding
the independent samples t-test and the repeated measures ANOVA are made, which means we
could make valid conclusions. Also the assumptions for the multiple regression analysis are
made after exclusion of the cluster symptoms of PTSD. We have also tried to explain the
practical importance of this study, by creating a theoretical framework using research and
meta-analytic work, which enabled us to support and reason our questions.
There are however also some limitations, which need to be taken accounted for and are
nuancing our findings. First the use of a sample size consisting out of 34 participants, which
could be argued as small, as before the inclusion criteria the data consisted out of 658 patients
over the course of three years, whom had finished either EMDR or NET. While implying the
inclusion criteria the assessments of the ROM causes for the lack of data. Meaning that the
needed two assessments before and after treatment has not included into the database. Also
12
the before and after assessments of the ROM has its limitations, because this means that on an
analytic level the independent samples t-test was used, where if more assessments would have
been conducted a repeated measures analysis could have been performed. The outcome of
both analysis might not have differ, however the repeated measures analysis could have given
us more information regarding the treatment development. Another limitation might be the
use of only two trauma-focused treatment, while others are not included, therefore the
outcome could have been influenced by other trauma-focused treatment such as TF-CBT.
The data does not fit the multiple regression analysis, as the overall model is
insignificant. Due the assumption of multicollinearity the three cluster symptoms of PTSD are
excluded from the model, because they highly correlated with one another. This was
suspected, as the cluster symptoms together make the overall score for PTSD. Furthermore,
the insignificance of gender and refugee status as predictor values might suggests that both
may not influence treatment outcome.
The results of this study might suggest that treatment outcome may not be influenced by
gender or refugee-status. For clinical practise this might implicate both men and females or
refugees and natives might benefit from trauma-focused treatment. Another suggestion can be
made regarding the ROM, which is to implement the ROM assessment more frequently,
which has both high research and clinical values. Research might value by more ROM
assessment as the course of PTSD during treatment could be evaluated and taken account for
in further studies. The clinical practise could benefit both patients as practiser, as both are
able to look upon the progress of the treatment and might give the patient insight in own
development and practiser insight in own therapy effect, where when needed the practiser
could change course when the ROM assessment suggest inefficacy of treatment.
Conclusions and additional directions
The present study contributes to the matter of prognostic factors regarding the treatment of
complex PTSD. We might tentatively conclude that TFT may contribute to the reduction of
symptom clusters of PTSD. We also may infer that neither gender nor refugee status influence
treatment response: thus males and females, as well as refugees and native patients may
benefit from TFT. The predictive value of the named prognostic factors could not be
identified.
The research on prognostic factors is of importance for the clinical practise and research
as this might positively influence the treatment responds, when treatment can be more
precisely implemented for relevant groups. Additional directions for further research to gather
more information on the matter might be comparing different treatments, such as EMDR and
13
NET concerning prognostic factors. This could add not only to the theoretical framework, but
also have practical importance. As such research could help people with complex PTSD more
effectively.
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