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Assignment #1
Systematic Review Summary
Diana Strock-Lynskey
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Citation: Roberts NP, Kitchiner NJ, Kenardy J,
Bisson JI. Multiple session early psychological
interventions for the prevention of post-traumatic
stress disorder. Cochrane Database of Systematic
Reviews 2009, Issue 3. Art. No.: CD006869.
DOI:10.1002/14651858.CD006869.pub2.
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Editorial group: Cochrane Depression, Anxiety and
Neurosis Group.
Publication status and date: Edited (no change to
conclusions), published in Issue 4, 2010.
Review content assessed as up-to-date: 31 July
2008.
Background
 The prevention of long-term psychological distress following traumatic
events is a major concern. Previous systematic reviews have suggested
that individual Psychological Debriefing (individual session delivery) is
not an effective intervention at preventing post traumatic stress disorder
(PTSD) (pg. 2 & 3).
 Recently other forms of intervention have been developed with the aim
of preventing PTSD and there has been an increased focus on providing
psychological intervention to everyone who has been exposed to a
traumatic event regardless of symptomatology. The issues of whom,
when, and what mode of intervention are matters that are at this time
contentious (pg. 3).
Overall Objective
 To examine the efficacy of psychological interventions aimed at
preventing PTSD in individuals exposed to a traumatic event but
have who have not been identified as suffering from any specific
psychological difficulties, in comparison with control conditions
(including usual care, waiting list conditions, and no treatment)
and other psychological interventions (pg. 3).
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This review used a common search strategy also utilized by the
Cochrane review of early interventions aimed at treating acute
stress symptoms (Roberts 2010).
The trials selected for this systematic review came primarily from
The Cochrane Depression, Anxiety and Neurosis Group (CCDAN)
which maintains two clinical trials registers as their editorial base
in Bristol, UK. The reference register contains over 24,000
reports of trials in DAN. Approx. 70% of these trials have been
coded and tagged to individual trials & are held in the
CCDANCTR-Register.
References to trials for inclusion in this broader database are
collected weekly and include generic searches of MEDLINE,
EMBASE, and PsyINFO.
Quarterly searches were conducted of the Cochrane CENTRAL.
Annual searches were conducted of PSYINDEX, LILACS, AMED
AND CINAHL.
Details of other trials were also extracted from international trial
registers, drug companies, and conference proceedings, and
other non-Cochrane systematic reviews and meta-analyses.
Source: Kitchiner, pg. 1 &5.
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Review of Reference Lists
◦ National Institute for Clinical Excellence PTSD
Guidelines and studies and articles were identified
in this search (NOTE: not specified here which ones)
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Hand Searching of Journals (2)
◦ Journal of Traumatic Stress
◦ Journal of Counseling & Clinical Psychology
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251 titles & abstracts were identified and 50
papers & all were reviewed in detail by the
two reviewers.
Personal Communications/Consultations
◦ 35 “key individuals”/”experts” in the field (does not
specify which fields they are experts in, does not
indicate what communications focused on)
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Diagnosis
= “stress disorder*” or PTSD
Intervention = therapy or intervention or counsel*
or debriefing
Age-group = adult or aged or “not stated” or
unclear
Duration of therapy = “1 session”
CCDANCTR = References
Free-text
= PTSD and Free-text = debrief* or
*therapy* or intervention* or counsel*
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Any multiple session early psychological intervention designed to
prevent symptoms of traumatic stress begun within three months of a
traumatic incident consisting of 2 or more sessions was eligible.
Any randomized two armed controlled trial was eligible (sample size,
language and publication status were not used to determine whether or
not a study should be included).
Participants did not have to be/were not blind to their allocation group
A psychological intervention was defined as any specified nonpharmaceutical intervention aimed at preventing the onset of PTSD
offered by one or more health professional or lay person, with contact
between therapist and participant on at least two occasions.
Eligible interventions included forms of psychological interventions that
focused on a specific theoretical model and non-pharmaceutical models
that did not focus or only partially focused on a theoretical model but
aimed to reduce symptoms of traumatic stress.
Participants viewed as suitable for inclusion were any adult individual
exposed to a traumatic event that is likely to meet criteria A1of the DSMIV (1994) for PTSD (but not necessarily diagnosed as having PTSD)
based on having experienced, witnessed, or been confronted by an
event/events that involved actual or threatened death to themselves or
others.
Studies of Non-pharmaceutical
psychological interventions based on a
specific theoretical model such as:
 Any individual or group psychological
intervention that utilized trauma
focused cognitive, behavioral, or
cognitive-behavior therapy (TF-CBT)
and exposure therapy (…or not…)
 Any individual or group psychological
intervention that utilized non-trauma
focused cognitive, behavioral, or CBT
therapy excluding exposure therapy
for including but not limited to stress
management.
 Individual psychological interventions
based on the use of Eye Movement
Desensitization & Reprocessing
(EMDR)
Studies of non-pharmaceutical
interventions not based or only partially
based in a specific theoretical model
And aimed at reducing symptoms of
Traumatic stress such as:
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Education and information giving
interventions focused on future
difficulties and advise about
constructive coping strategies
“Stepped care” programs that focused
on offering intervention in a stepped
care manner based on continuing
needs
Any other intervention aimed at
enhancing coping/overall well-being
such as OT, an exercise-induced
intervention, or a guided self-help
intervention.
Trials that included psychological
interventions.
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Single session interventions were excluded because they were the
focus of a separate review (Rose 2002). The authors noted that one
study included in this earlier review did focus on more complex
psychological intervention but was excluded from this current
review as the study design was only partially randomized.
Other more recent studies utilizing single session interventions
were also excluded based on their focus (Resnick 2005; Rose 1999;
Rothbaum submitted; Turpin 2005).
Early psychological interventions aimed at treating individuals who
were identified as symptomatic (Acute Stress Disorder, Acute PTSD,
Depression) were excluded due to a separate review that was being
conducted at the time of this review (Roberts 2010).
Studies involving non-adults were excluded (pg. 4).
7 studies awaiting classification were excluded/put on hold
because the authors never responded to inquiries from the
reviewers of this study. The authors noted that they expected that
they would rerun electronic searches within 12 months of this
review and attempt to gather more info from these authors at that
time (pg. 8).
Pharmaceutical interventions for PTSD were excluded also due to a
separate review underway at the time of this review.
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Interventions offered to mothers
who had experienced traumatic
births (3 = 1 from Australia
focused on interpersonal
counseling and 2= from Sweden
focused on group counseling)
Individuals who had road traffic
accidents w/pulse rates of at least
95 beats per min. upon admission
to emergency room (2 = Israel
and both focused on a 2 session
memory restructuring intervention
and used a supportive listening
intervention for comparison)
1 study of individuals who had
experienced major physical
trauma and been admitted to a
trauma center (1= Australia &
used individual counseling)
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1 study of victims of armed robbery
who reported experiencing intense
fear, helplessness or horror during of
after the robbery (1 = Canada &
focused on an adapted debriefing
intervention used with individuals)
1 study of bus drivers who had
been assaulted ( 1= France & = CBT
interventions up to Ind. 6 sessions)
2 studies of individuals exposed to
a range of “civilian traumatic
experiences” (1= Netherlands that
focused on individual counseling) and
1=USA with same type of trauma but
focus was on hospitalized inpatients
(that provided a joint counseling &
collaborative care intervention focus)
1 study of caregivers of children newly
diagnosed with cancer (1= USA =
CBT+ Family intervention)
NOTE: The data on this slide was not
readily available in this format and had
to be created for this presentation).
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The methodological quality of each study was assessed independently by
each reviewer using the criteria outlined in the Cochrane Handbook.
Reviewers then identified an additional 19 criteria that would be more
relevant to use for review of a psychological intervention.
Seven of these criteria included “gold standards” recommended by Foa
(1997) for RCT’s investigating interventions for PTSD and included: clearly
defined target symptoms, use of reliable and valid outcome measures, use
of blind & independent assessors, assessor reliability, manualised special
and replicable treatment, concealment of allocation, and treatment
adherence.
Four criteria were drawn the work of Hertlein (2004) and included: nonconfounded conditions, use of multi-modal outcome measures, reported
level of therapist training, and use of a control or comparison group. One
criteria, a clear definition of the population to receive intervention, was
drawn from the work of Rose (2002).
The following eight criteria were drawn from the Moncrieff scale (2001):
adequate follow-up, report of side effects, report of exclusions and
refusals, compatibility, intent to treat analysis, presentation of results,
power calculation, appropriate statistical analysis, and justified
conclusions. NOTE: This adds up to 21 criteria.
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A data extraction sheet was designed that was then
entered into Review Manager Software.
Reviewers then completed an analysis of the primary
outcome measure = 5 individual studies (n= 479), which
included less RCT’s and participants, were selected for
an analysis which focused on:
◦ Rates of severity of PTSD and/or trauma stress
symptoms (rated by a clinician using the PTSD scale)
◦ Individual self-ratings by both treatment and ITT
groups (using standardized measures such as the
Impact of Life Event Scale or the Davidson Trauma
Scale, or the Post-Traumatic Diagnosis Scale)
◦ Rates of actual PTSD diagnosis among those exposed
to trauma determined by clinician using criteria
outlined in the DSM-IV (Table 3, pg. 11).
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Next, an Analysis/Comparison I, was completed that focused
on secondary outcome measures involving 8 studies = any
psychological intervention vs. waiting list/usual care. A metaanalysis was able to performed for 6 of these studies . This analysis
included 10 comparisons as follows:
Analyses 1.1 & 1.2: Comparison of PTSD Diagnosis post-treatments
for completer & ITT group (pg. 32-34) and Analyses 1.3 & 1.4:
Comparison of 3-6 month follow-up for both groups, (pg. 33-34)
(Risk ratio and Effect Size, pg. 30-31).
Analyses 1.5 & 1.6: Comparison of severity of PTSD symptoms:
post-treatments for completers (self-report) (Weighted/Std. Mean
Dif.) and 3-6 month follow-up for completers (self-report) (pg. 3536) (Same).
Analysis 1.7:Outcome – Anxiety, post-treatment (pg. 37); Analysis
1.8:Outcome – Depression, post-treatment (pg. 38); Analysis 1.9:
Outcome – Depression – 3-6 month follow-up (pg. 39) (Same).
NOTE: Severity of self-reported depression were measured by the
Beck Depression Inventory; severity of self-reported anxiety
symptoms using the Beck Anxiety Scale or the Spielberger StateTrait Anxiety Inventory and Analysis 1.10 Both groups: leaving the
study for any reason (pg. 40).
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Continuous outcomes were analyzed using weighted mean difference
(WMD) when all trials had measured outcome on the same scale. When
some trials measured outcomes on different scales, standardized mean dif.
(SMD) was used. (pg. 6).
Relative risk (RR) was used as the main categorical outcome measure as
this is more widely used than odds ratio (OR) in health related practice. All
outcomes were presented using 95% confidence intervals.
For trials with a crossover design, only results from the first randomization
period were considered. If the trial was a three (or more) armed trial,
consideration was given to undertaking pair-wise meta-analysis with each
arm, depending upon the nature of the each intervention relevance to
review objectives (pg. 6).
For missing data, when intention to treat (ITT) data were available, these
were reported. Where partial ITT data and partial completer data were
available, separate analysis was undertaken. Completer only analysis was
performed when this was the only data source available. For continuous
data when only the SE or t-statistics or p values were reported, SDs were
calculated (pg. 6).
Regarding heterogeneity, A visual inspection using forest plots was first
utilized. Heterogeneity between studies was also measured. When mild (Isquared of less than 30%) or moderate heterogeneity was identified (Isquared between 30-50%) a fixed-effect model was used to synthesize
results. When “notable” heterogeneity (greater than 50%) was indicated, a
random-effects model was used. In cases where significant heterogeneity
was found to be present, the authors noted that they attempted to explain
the variation (pg. 6-7).
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Subgroup analysis and investigation of heterogeneity: the reviewers
decided a priori that the following possible causes of clinical
heterogeneity would be explored if sufficient data allowed for
analysis: 1) # of treatment sessions taken (2-6 vs. 7 or more); 2)
time after index event exposure to when the intervention begins (1
month (4 weeks) or less vs. 1-3 months (5 to 13 weeks)); 3) type of
traumatic event (combat related trauma vs. rape and sexual assault
vs. other civilian trauma); 4) participant characteristics (males
versus females); and 5) symptom severity as measured by clinical
measures at time 1 (mild/moderate versus severe) (pg. 7).
Sensitivity Analysis: It was also decided a priori that sensitivity
analysis would explore possible causes of methodological
heterogeneity if sufficient data allowed as follows: 1. trials
considered most susceptible to bias would be excluded based
on the following quality assessment criteria (those with unclear
allocation concealment, high levels of post-randomization losses
(more than 40%) or exclusions; and where unblinded outcome
assessment or blinding of outcome assessment was uncertain) and
2. use of intention-to-treat analysis versus completer outcomes
would be undertaken depending on available data.
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Next, a comparative analysis/Comparison 2 was
conducted of “Any intervention vs. other intervention”.
This analysis focused on two studies included in the
systematic reviewed conducted by the same researcher
that had compared memory structuring intervention
with supportive listening. However it was determined
that there was insufficient data to conduct a metaanalysis.
A separate analysis was also conducted of the one
study that related to participants who had received a
PTSD Diagnosis at three months post trauma. No
significant difference was observed between treatment
and the control condition at 3 month follow-up (n=17;
RR 0.28, 95% CI 0.04 to 2.02).
Leaving the study early was also evaluated for each of
these studies. No drop-outs were reported in either
the treatment or the control condition.
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11 studies were selected for review with a total of 941 participants.
8 studies with 774 participants provided actual data for meta-analyses.
The majority of these study results were based on completer data only
(rather than both ITT and completer data).
When comparing what ITT data was available to the completer data, the
reviewers reported that there was no observable difference between
treatment and control conditions on primary outcome measures for
interventions at initial outcome (k=5, n=479; RR 0.84; 95% CI 0.60 to
1.17) with the following exceptions:
There was a trend, for those who had self-reported PTSD symptoms
prior to treatment towards increased self-report of PTSD symptoms at
3 to 6 month follow-up in those who received an intervention (k=4,
n=292; SMD 0.23; 95% CI 0.00 to 0.46. The reviewers identified that
there was also a trend that just failed to reach statistical significance
for no intervention to result in less self-reported PTSD symptoms at 36 month follow-up than for those that participated in a multiple
session intervention.
The most frequent intervention utilized were that of individual/
interpersonal counseling and a few studies that utilized CBT or a
variation of this approach. These interventions showed no statistically
significant differences between impact on ITT and completers. Two
studies were also analyzed separately that compared a memory
structuring intervention against supportive listening. There was no
evidence supporting the efficacy of either of these interventions.
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The reviewers did note in the follow-up discussion of the results that one
study focusing on anxiety reported a significant decrease in intrusive
symptoms and anxiety in their treatment groups but data provided in their
paper did not permit inclusion in the meta-analysis (not a RCT).
In addition to this, one study that included individuals that received a
counseling intervention that used an adapted form of critical incident
debriefing showed an increase in symptoms, when compared to those in
control conditions, tended to be doing worse at the six month follow-up.
Two possible reasons for this finding were provided by the reviewers:
1) this study included individuals with a psychiatric history prior to the
occurrence of the traumatic event and 2) the prior findings of a systematic
review (Rose 2002) that concluded that single Critical Incident Debriefing
interventions are associated with worse outcomes at longer term follow-up.
At the same time the reviewers noted that such conclusions need to be
approached with caution given a 3rd factor, the contradictory findings for
PTSD diagnosis in other studies. The reviewers also noted that absence of
tolerability assessment was a key shortcoming in the RCTs identified for
this study and one that has previously been noted in psychological
treatment studies of chronic PTSD (Bisson 2007b).
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The statistical and methodological reasons for these contradictory
results were noted as “unclear”. In the summary discussion, some
possible reasons given = heterogeneous nature of the populations,
small sample sizes, diversity of traumatic events experienced.
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Combined with the heterogeneous nature of the interventions, the
reviewers indicated that results in uncertainty that still remains with
regard to the efficacy of specific interventions (pg. 12-14).
The reviewers also noted that unfortunately the limited number of
trials relating to methods of interventions meant that sensitivity
analyses could not be performed in a meaningful way to explore
these issues further (pg. 13).
The reviewers also noted that statistical heterogeneity was apparent
in several analyses (of interventions), with the I² value demonstrating
inconsistencies in the outcomes of some tria ls that were grouped
together.
When statistical heterogeneity was identified the reviewers used
a random effects model as opposed to a fixed effect model to
calculate more conservative confidence intervals. Based on this, the
reviewers concluded that all trials were essentially trying to measure
the same thing and that it was still worthwhile for them to
summarize their combined results (pg. 13).
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Final conclusion = there is currently little evidence to support
the routine use of psychological interventions for everyone
following a traumatic event and some multiple interventions,
much like single intervention CIDB, may have adverse effects.
More RCT’s could be subjected to further evaluation with
particular emphasis on preventative CB interventions which have
not been adequately investigated. However, the absence of
effect, and trend towards a worse outcome after use, suggests
great caution is still needed.
Future research should focus on alternative interventions for
PTSD (social, psychological, neurobiological), interventions for
couples and families, forms of community interventions, and
interventions aimed at improving coping skills and enhancing
positive and helpful behaviors should be explored.
Factors such as optimal time to intervene, adverse effects, and
tolerability for treatment should also be explored (pg. 14).
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The objective of the review was stated as “to examine the efficacy of
multiple session early psychological interventions commenced within three
months of a traumatic event aimed at preventing PTSD” (pg. 1). In a
discussion that followed this objective, it was also noted “epidemiological
research suggests that a third of individuals who develop acute PTSD
remain symptomatic for six years or longer (Kessler 1995)” (pg. 2).
The stated objective for this review was not to determine if everyone who
experiences a traumatic event should receive a psychological intervention
but rather , if multiple session EPI within 3 months prevented PTSD.
The reviewers also did not identify a specified time limit during which
participants needed to demonstrate a significant decline or increase in
symptoms as an indicator for determining effectiveness and prior research
seems to suggest otherwise. However, none of the studies reviewed
provided services beyond a 3 month time frame and follow-up efforts only
extended to 3-6 months (see Table 1, pg. 10).
Reviewers were only able to identify data on the #’s of sessions for some
studies (which ranged anywhere from two sessions to eight sessions with
no consistent pattern) and no data on this for others so it appears that
they ended up “backing into” indirectly evaluating effectiveness based on
time frames dictated by the studies selected/# of sessions offered.
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Several quasi-experimental studies were excluded because they did not
utilize RCT’s. Yet several of the studies that ended up being utilized for
this review did not have adequate ITT/control group data to allow for
more suitable analyses. The search terms used, populations focused on,
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and sources utilized were very narrow in scope.
The reviewers noted there is now a large body of literature to show that
traumatic experience can cause significant psychological difficulties for
large populations through events such as natural and man made
disasters, military combat and other types of traumatic events (pg.2)
and that traumatic events can have a significant impact on families’ and
communities’ abilities to cope (pg. 15) but only one study selected
involved a family and none of the studies selected focused on groups or
communities. Crisis intervention and emergency/disaster response are
also two key areas. Perhaps if a broader search strategy had been used it
might have yielded a broader range of studies and data for analysis.
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The reviewers ruled out studies that included critical incident debriefing
based on a prior systematic review (Rose 2002) that focused on single
session use. This review took place several years ago and has not been
updated since and this intervention is still used fairly frequently. Given
this, inclusion of CIDB multiple session use would seem appropriate. The
rationale for excluding this intervention does not seem on-target.
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The primary outcome measure identified was preventing psychological
difficulties and PTSD for individuals who were not yet symptomatic for
PTSD but were considered to be in a “general pool” of people at risk only
based on the nature of the event they experienced.
Yet, 2/3 of participants were either assessed by a clinician or selfreported as having symptoms of PTSD including 17 participants who
were actually given a PTSD diagnosis. Given this, perhaps the objective
of the review should have been to focus on the “general pool” and those
not yet experiencing symptoms of PTSD but who may have symptoms of
anxiety, depression, or traumatic stress.
Since the reviewers chose to broaden the focus to include those with a
PTSD diagnosis, perhaps they should the inclusion criteria should have
been broadened to allow for studies that focused on individuals with a
diagnosis of Acute Anxiety Disorder, Acute Panic Disorder and
Depression that also related to PTSD.
The reviewers noted that they chose not to include Acute Anxiety Order
and PTSD studies because of the reviewers of this study was conducting
a separate review on this focus. However, it seems that this disorder and
the other types noted should have included in this review, regardless, to
ensure consistency. Is it a requirement that reviews can never cross over
in any way in their focus? Do reviews have to be this compartmentalized?
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The reviewers noted that heterogeneity was a factor that influenced
difficulties with data analysis based on the types of trauma events
experienced by the range of study participants. However, the additional
possible impact of cross-cultural variations (the studies spanned 6
different countries) was not mentioned. For example, it seems like
factors such as how traumatic stress is demonstrated and how treatment
is approached within and across cultures could also influence both
approaches and outcomes of interventions. Are such aspects ever
accounted for in reviews and by what methods?
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Assessor reliability was “no” for every single study. Only 3 studies
indicated a response of “yes” to treatment adherence (pg. 9) Both of
these aspects would seem to undermine the credibility of both the
interventions being evaluated and their impact on participants. Yet,
these matters were not raised in the summary. Should they have been?
Based on all of these aspects, OTHER THAN to conclude that
interpersonal counseling is not a useful intervention for this type of
treatment situation, it does not seem that reviewers had adequate data
to support their objective statement and certainly not to reach the
broader conclusions noted (i.e. external validity). Some other possible
interpretations findings (beyond what was noted) : that more attention
needs to be given to determining the minimum # of sessions that might
be needed depending on severity of symptoms, that providers need to
consider exploring the use of a broader range of interventions (beyond
counseling), and that the development/piloting of a possible screening
device for use with the GP could also be beneficial for future research.