Tutor: MathematicsExpert Only

Traumatology 19(3) 171 –178 © The Author(s) 2012 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1534765612459891 tmt.sagepub.com

Article

Concern over the best methods to prevent and treat combat- related posttraumatic stress disorder (PTSD) in military ser- vice members and military veterans has been of particular interest with the resurgence of military service members who are serving multiple tours in Iraq and Afghanistan. Preventa- tive programs such as comprehensive soldier fitness (Casey, 2011) acknowledge the need for the military services to have a more frank discussion with their service members about PTSD. The stigma within the military of a PTSD diagnosis prevents many service members from seeking treatment, even when they recognize the symptoms of PTSD in them- selves. While military programs, such as the Department of Veterans Affairs, have sought to educate service members and their families about the importance of seeking treatment for PTSD, the threat of having a diagnosis of PTSD on their service record stops many service members from seeking help. Some have been able to seek treatment outside of the military health care system, but such treatment can be costly. Another related population is military veterans who, like their present-day counterparts, did not seek treatment or for whom no appropriate treatment was available.

The preferred treatment for anxiety disorders is exposure therapy (Powers & Emmelkamp, 2008), also known as pro- longed or gradual exposure therapy. Exposure therapy is a type of behavior therapy where the client is taught cognitive and behavioral techniques such as progressive muscle relax- ation, breathing exercises, recognition of automatic thoughts and schemas, and cognitive restructuring (Pull, 2005). The client is taught to utilize these interventions while the thera- pist gradually exposes the client to the cause of anxiety, increasing the intensity of exposure as the client is able to tolerate in order to help the client become more accustomed to the stimuli-evoking anxiety. Clients also undertake self- conducted exposure-based exercises as homework in between formal treatment sessions. Two types of exposure therapy have dominated the field: in vivo therapy, where the

459891TMTXXX10.1177/153 4765612459891TraumatologyNelson

1Florida State University, Tallahassee, FL, USA

Corresponding Author: Rebekah J. Nelson, Florida State University, 296 Champions Way, University Center, Building C, Tallahassee, FL 32306, USA. Email: [email protected]

Is Virtual Reality Exposure Therapy Effective for Service Members and Veterans Experiencing Combat- Related PTSD?

Rebekah J. Nelson1

Abstract

Purpose: Exposure therapy has been identified as an effective treatment for anxiety disorders, including posttraumatic stress disorder (PTSD). The use of virtual reality exposure therapy (VRET) in the past decade has increased due to improvements in virtual reality technology. VRET has been used to treat active duty service members and veterans experiencing posttraumatic stress symptoms by exposing them to a virtual environment patterned after the real-world environment in which the trauma occurred. This article is a systematic review of the effectiveness of using VRET with these two populations. Method: A search of 14 databases yielded 6 studies with experimental or quasi-experimental designs where VRET was used with active duty service members or veterans diagnosed with combat-related PTSD. Results: Studies show positive results for the use of VRET in treating combat-related PTSD, though more trials are needed with both active duty service members and veterans. Conclusions: VRET is an effective treatment, however more studies including random assignment are needed in order to show whether it is more effective than other treatments. There are still many barriers that the use of VRET with military populations would need to overcome in order to be widely used, including helping veterans become accustomed to the technology; assisting veterans who have spent a longer period of time avoiding anxiety-inducing stimuli in accepting an initial increase in anxiety; clinician concerns about the technology interfering with the therapeutic alliance, and clinician biases against the use of exposure therapy in general; and high treatment dropout rates.

Keywords

combat, posttraumatic stress disorder, service members, veterans, virtual reality exposure therapy

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

172 Traumatology 19(3)

therapist and client are able to experience exposure to anxi- ety-evoking stimuli in increasingly naturalistic settings; and imaginal exposure therapy, where the therapist leads the cli- ent in imagining the cause of anxiety. Usually exposure ther- apy (ET) in imagination is followed by real-life exposure. These two types of exposure therapy are sometimes poorly tolerated by service members and veterans who have com- bat-related PTSD because of the distinctness of the settings in which the trauma occurred, and because of the tendency of clients to suppress thoughts that activate PTSD symptoms (Riva et al., 2010).

A relatively new exposure-based treatment for PTSD that has gained attention in the media and the therapeutic com- munity is the use of virtual reality programs. Using virtual reality in place of real-life or imaginal exposure therapy allows clients to receive and process exposure to traumatic events in a relatively safe environment. Virtual reality expo- sure therapy (VRET) has been tested with persons experi- encing PTSD symptoms in multiple trials and with many different causes of anxiety (Gerardi, Cukor, Difede, Rizzo, & Rothbaum, 2010; Pull, 2005). In their meta-analysis on the use of VRET for anxiety disorders, Powers and Emmelkamp (2008) found VRET to have a slightly more powerful effect than did real-life exposure treatment.

This review will assess studies of the effectiveness of VRET when used to treat service members and military vet- erans diagnosed with combat-related PTSD. It will also con- sider the practical use of the technology, including the cost of treatment and the possible application of VRET in the assessment and prevention of PTSD in active duty soldiers.

PTSD is a type of anxiety disorder brought on by experi- encing or witnessing a traumatic event or events. Traumatic events are defined by the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; American Psychiatric Association, 2000) as events “that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others” (p. 467). The response to the trauma also yields feelings of hopelessness, fear, or horror. The traumatic event must be reexperienced in some way, such as through nightmares or physical reactions to events resembling the trauma. There must also be an avoidance of stimuli that cause thoughts about the trauma and increased arousal, such as hypervigilance. These symp- toms must have lasted for more than 1 month, and must be causing clinically significant distress for the individual.

Therapists using VRET to treat PTSD seek to simulate a virtual world that is as similar as possible to the real-world environment in which the traumatic event occurred. This is referred to as a “sense of presence” in the virtual world, or the level to which clients actually feel the virtual environ- ment mirrors reality. In a qualitative study of clinician perceptions about VRET (Kramer et al., 2010), clinicians expressed concern that the virtual environment would not be

realistic enough in order to trigger and then reduce anxiety. However, in their evaluation study of the realism of two vir- tual Iraq scenarios, Reger, Gahm, Rizzo, Swanson, and Duma (2009) conducted a convenience sample study with 93 soldiers not diagnosed with PTSD to see if the soldiers, who had been deployed to Iraq one or more times, felt this sense of presence. A majority of the soldiers rated the convoy sce- nario (86%) and the city environment (82%) from adequate to excellent.

VRET uses several technology-based methods to engage all five senses of the client, making the exposure feel as real- istic as possible. The technology used generally includes a “controlled delivery of sensory stimulation via the therapist, including visual, auditory, olfactory, and tactile cues” (Gerardi et al., 2010, p. 299). Visual effects include being able to change the time of day, weather, number of pedestri- ans and vehicles, street debris, Humvees, planes, and heli- copters clients see within the virtual world. Most of the machines include an orientation tracker, which allows clients to move about the virtual environment via headgear that responds to the movements of the participant. Olfactory senses are also engaged using scent palettes, which blow smells such as spices or burning rubber, and are controlled by the therapist. The therapist can also include sounds such as sirens, people crying, gunshots and mortars, helicopters, improvised explosive devices, rocket-propelled grenades, car bombs, and sounds of an insurgent attack. In their narra- tive review of the many uses of VRET, Gerardi et al. (2010) describe two scenarios available in their virtual Iraq:

The city incorporates scenes such as marketplaces, security checkpoints, mosques, apartment buildings that can be entered, and rooftops that can be accessed. The Humvee scenario includes a desert setting with overpasses, checkpoints, debris, broken-down struc- tures, and ambushes that can be introduced. (p. 303)

Finally, clients’ seats are manipulated to create tactile vibrations in order to mimic a car ride, helicopter ride, or an explosion. An example of the equipment and virtual reality scenarios utilized in VRET can be seen in many media reports on the subject, such as a news report conducted by the Canadian Broadcasting Corporation on the costs and benefits of VRET (Virtual Iraq Afghanistan Media Story CBC, video file).

Similar virtual settings can be created for veterans of wars in other areas of the world. Specific to this article are virtual environments that mimic settings in Vietnam for veterans of the Vietnam War, and in Africa, where a war was fought by Portuguese soldiers in Africa between 1963 and 1970.

As explained in Rothbaum, Hodges, Ready, Graap, and Alarcon’s (2001) article on the use of VRET with Vietnam veterans, VRET treatment spans several weeks of therapy,

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

Nelson 173

Table 1. VRET Equipment Needed to Set Up a VRET Environment.

Two Pentium 4 computers with 1 GB RAM each DirectX 9 128 MB DirectX 9-compatible NVIDIA 3D graphics card Ethernet cable Head Mounted Display and Navigation Interface (eMagin z800) Numerical Design Limited’s Gamebryo rendering library Alias’ Maya 6 and Autodesk 3D Studio Max 7 Envirodine, Inc. Scent Palette Logitech force-feedback game control pad and audio-tactile sound transducers from Aura Sound Inc.

Table 2. VRET Reviewed Studies.

Study Year Intervention Study population Study design Primary outcome

Ready et al. 2006 VRET Vietnam veterans diagnosed with PTSD (n = 14)

OXO Change in CAPS scores for participants were statistically significantly different at posttreatment, 3 month, and 6 month follow up; BDI scores were statistically significantly different at posttreament and 6 month follow up, but not at 3 month follow up

Gamito et al. 2010 VRET vs. exposure in imagination vs. waiting list

Portuguese war veterans (n = 10)

VRET (n = 5) EI (n = 2) Waiting list (n=3)

R OXO R OYO R O O

CAPS scores were not statistically significantly different; IES-R, BDI, and SCL-90-R scores were collected only for the VRET group

Ready et al.

2010 VRET vs. present- centered therapy

Vietnam veterans with combat-related PTSD (n = 11)

R OXO R OYO

Both VRET and PCT lowered mean CAPS scores at posttreatment and follow up, with VRET yielding higher levels of improvement

McLay et al.

2011 VRET vs. treatment as usual

Active duty soldiers from two hospital sites with PTSD related to their duties in Iraq or Afghanistan (n = 19)

R OXO R OYO

No significant difference between the two groups before or after treatment; however, there was a significant (p < .05) difference in the mean CAPS change score over the course of treatment

Reger et al. 2011 VRET, adapted from prolonged exposure manual

Active duty soldiers (n = 24), diagnosed with PTSD (n = 18), or Anxiety NOS (n = 6)

OXO At posttreatment, 62% (n = 15) had reliably improved on the PCL-M

McLay et al. 2012 Virtual reality exposure therapy (VRET)

Active duty soldiers from a naval medical center and a marine corps base (n = 42) with multiple drop outs before session 4 (n = 12) and after session 4 (n = 10)

OXO PCL-M scores between baseline and posttreatment were statistically significant (p < .0001), as were PHQ-9 and BAI scores at baseline and posttreatment. For n = 17 participants, scores at 3 month follow up were also significantly different from baseline on the PCL-M, PHQ-9, and the BAI

generally meeting twice a week for 90 to 120 min each ses- sion. The first session of VRET treatment is spent in assess- ing clients and gathering information about the traumatic event they experienced. Sessions 2 and 3 are spent in accli- matizing clients to the virtual reality equipment and environ- ment, and in teaching clients cognitive behavioral interventions to practice when their symptoms increase, such as breathing and relaxation techniques. Further therapy

sessions are spent in using the virtual environment to expose clients to traumatic memories while they describe the events in detail. Homework assigned to clients generally includes listening to recordings of the therapy sessions while practic- ing cognitive behavioral interventions learned in therapy.

Some who have been working on virtual reality technol- ogy have anticipated the use of it as an assessment tool to determine whether a soldier is emotionally and mentally fit

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

174 Traumatology 19(3)

to return for another tour (McLay et al., 2012). Others (Kraft, Amick, Barth, French, & Lew, 2010) also anticipate the use of virtual reality in reassessing the driving ability of combat service members returning from Iraq or Afghanistan who have been diagnosed with PTSD or traumatic brain injury (TBI), as these two disorders may critically affect returning soldiers’ ability to drive. In these ways, virtual reality tech- nology may benefit soldiers as an assessment tool, rather than solely a treatment for PTSD.

VRET has also been looked at as a prevention tool. Stetz, Long, Wiederhold, and Turner (2008) conducted a study in which virtual reality and stress inoculation training were used to try and prevent medics who would be serving in Iraq or Afghanistan from later developing PTSD. Stress inocula- tion training consists of exposing the participant through virtual reality technology to traumatic events they may encounter in their future service in hopes that when they encounter similar traumatic events in reality they will be able to use their practiced cognitive behavioral skills to lessen their chances of developing PTSD in the future. While no distal measures of whether the stress inoculation training provided in Stetz et al. (2008) are given, posttests suggest exposing military medics preemptively to stressful situations may harden them against trauma. Such a preventative effort may be useful to all military personnel, as Reger et al. (2009) report that 67% of a convenience sample (n = 93) of military service members had provided aid to persons who were wounded during their combat experience. Exposure to such secondary trauma can sometimes serve as the initiating event triggering the onset of PTSD; however, if service members were given preventative virtual reality stress inoculation training, their chances of developing PTSD due to this expo- sure may decrease.

One of the concerns of implementing virtual reality ther- apy on a wide-scale basis is the approximate cost of purchas- ing and setting up the virtual reality equipment and in training therapists to use the equipment effectively. In their prelimi- nary results utilizing virtual reality technology with active duty soldiers with PTSD, Rizzo, Reger, Gahm, Difede, and Rothbaum (2009) approximate some of the costs of setting up an adequate amount of virtual reality equipment in order to make the virtual environment realistic enough to help effect change. However, the authors only provide actual dol- lar amounts regarding the Head Mounted Display (US$1500) and the Logitech control pad (<US$120) that creates vibra- tions in the seat of the participant. Table 1 is a list Rizzo et al. (2009) give of equipment needed to set up a virtual reality therapy environment. In an interview with CBC news, Rizzo (Virtual Iraq Afghanistan Media Story CBC, video file) estimates the total cost of virtual reality hardware to be approximately US$15,000, stating that the computer soft- ware for conducting VRET can be obtained through him at no cost.

Wood et al. (2009) articulate the possible financial ben- efits implementing virtual reality technology could have if the military were saved the money of having to replace

service members who would have left the military due to PTSD symptoms. They estimated that the training cost sav- ings for the 12 participants in their study would be just under US$330,000, whereas the training cost savings of treating PTSD with treatment as usual would be close to US$193,000.

Pull (2005), Riva et al. (2010), and Gerardi et al. (2010) state that VRET may be more cost effective than imaginal or real-life exposure therapy because it can be less time- consuming. This may be because the technological equip- ment allows the clinician to have greater control over the magnitude of exposure in a virtual environment than they would have in trying to help the client imagine graded images of the trauma or feared object, thus taking less time overall to treat clients. Using virtual technology may also be less costly than trying to have a real-life experience with the client. For example, Gerardi et al. (2010) cites the cost to the patient of having a virtual experience with flying versus the cost of paying for a genuine flight.

Method Search Strategy

Academic Search Complete, JSTOR, Applied Social Sciences Index and Abstracts (ASSIA), Computer and Information Systems Abstracts, ERIC, ProQuest Dissertations, and Theses (PQDT), PsycINFO, Social Services Abstracts, Sociological Abstracts, Social Sciences Citation Index, Web of Knowledge, Web of Science, Military and Government Collection, and Dissertation Abstracts were searched in order to find studies pertaining to the topic. While the gray litera- ture was not specifically searched, efforts were made to obtain copies of articles and conference proceedings that were a result of the search strategy. Where possible, search terms were limited to abstracts. The search terms used for this review were virtual and realit* and (military or veteran*) and (PTSD or posttraumatic or post-traumatic). A flow chart (Figure 1) depicts the disposition of retrieved articles.

Data Collection and Analysis Methods While multiple case studies were found on this topic, only experimental and quasi-experimental studies looking at the use of VRET as a treatment for military service members or veterans experiencing combat-related PTSD will be included. The literature search yielded 100 studies. Seventy-one were ineligible based on review of the title (including repeats of previously acquired studies), and a further 16 were excluded after reviewing abstracts. Following a full-text review, seven more studies were excluded because they were found to be preliminary results of studies already acquired, the text or pertinent information was unavailable, or the study was ana- lyzed in more than one of the resulting studies and the article with the most information was chosen, leaving a total of six studies to include in the review (Table 2).

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

Nelson 175

Common Measures Used to Assess PTSD in Military Service Members The first, most common measure used in studying the effec- tiveness of treatment for PTSD is the Clinician Administered PTSD Scale (CAPS; Gamito et al., 2010; McLay et al., 2011; Ready, Gerardi, Backsheider, Mascaro, & Rothbaum, 2010; Ready, Pollack, Rothbaum, & Alarcon, 2006). The CAPS is a measure that assesses the frequency and intensity of PTSD symptoms. Another measure commonly used with military service members is self-report PTSD Checklist, Military Version (PCL-M; McLay et al., 2012; Reger et al., 2011). The Impact of Events Scale Revised (IES-R; Gamito et al., 2010) is a self-report instrument that measures PTSD symptoms of avoidance, intrusion, and hyperarousal, and the Symptoms Checklist Revised (SCL-90-R; Gamito et al., 2010) is used to measure psychopathology. Finally, the Patient Health Questionnaire-9 (PHQ-9; McLay et al., 2012) and the Beck Depression Inventory (BDI; Gamito et al., 2010; Ready et al., 2006) are used to measure depres- sion levels in clients, while the Beck Anxiety Inventory (BAI; McLay et al., 2012) is used to measure anxiety levels in participants.

Therapists also use what are called Subjective Units of Discomfort/Distress Scale (SUDS) when using VRET. SUDS are generally not tracked or measured for experimen- tal purposes, but are used to understand how the client is responding in the moment to the level of exposure in the virtual reality environment, and to decide if the level of

exposure should be increased or decreased based on partici- pant reactivity. Physiological monitoring through biofeed- back is also often used to monitor client response to the virtual environment and, in one study in this review (Wood et al., 2008) was used to measure the effectiveness of VRET.

Results VRET With Active Duty Service Members

In their randomized controlled trial of VRET with active duty soldiers, McLay et al. (2011) used a convenience sam- ple to locate potential patients. They assigned 20 service members to VRET (n = 10) or to treatment as usual (n = 10, with one participant not completing postassessment tests) using random assignment, and used the CAPS as their outcome measure. While the VRET intervention appeared to follow the standard VRET treatment protocol, the treatment as usual group was not assigned to any particular treatment. Rather, they were assigned to receive one or more of the treatments available for PTSD provided by the two hospital locations, which included prolonged exposure (PE) therapy, EMDR, group therapy, psychiatric medication management, substance rehab, and inpatient services. Unfortunately, only the number of mental health visits, and not what type of treatment the TAU patients were receiving, was tracked. The findings for this study may not, therefore, truly reflect the comparison between a VRET group and a TAU group, as we are unsure what type of treatment the TAU group spe- cifically received. Also, the TAU group was, at some point, changed to a waiting-list group. It is unclear at what point this information was given to TAU group members, which may have affected their confidence in the TAU treatment they received. McLay et al. (2011) found seven out of ten of the VRET patients improved at least 30% on their CAPS scores from pretest to posttest. There was no significant dif- ference between CAPS scores after treatment; however, the authors found a significant difference (p < .05) in the change from pretest to posttest mean scores between the VRET group (M = 35.4, SD = 24.7) and the TAU (M = 9.4, SD = 26.6) group, favoring VRET.

Reger et al. (2011) conducted a convenience sample study with 24 active duty soldiers diagnosed with PTSD (n = 18) or anxiety NOS (n = 6) who had been deployed at least once to Iraq or Afghanistan. The service members had either requested to receive VRET as a treatment or had received previous treat- ment for their disorder that was unsuccessful. The VRET was based on a training manual for the conduct of PE, delivered by a clinical psychologist with formal training in both VRET and PE. Patients received treatment a mean of 27.8 months (SD = 17.3) after the trauma, and received an average of 7.4 (SD = 3.3) treatment sessions. Researchers used the self-report PCL-M to measure treatment outcomes, and found patients reported a significant (p < .001) improvement in PTSD symp- toms from pretest (M = 60.92, SD = 11.03) to posttest (M = 47.08, SD = 12.7), with a large effect size (Cohen’s d = 1.17).

Figure 1. Search strategy results for VRET treatment for military service members and veterans with PTSD.

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

176 Traumatology 19(3)

A quasi-experimental convenience sample study of 20 active duty service members (McLay et al., 2012) used the PCL-M, PHQ-9, and BAI to measure PTSD symptoms, depression, and anxiety. Their study revealed a large effect size (Cohen’s d = 1.34) between baseline PCL-M scores (n = 20, M = 53.8, SD = 9.6) and posttreatment (M = 35.6, SD = 17.4) scores. For n = 17 participants, scores on the PCL-M also showed a large effect size (Cohen’s d = 2.17) between baseline (M = 53.8, SD = 9.6) and 3-month follow up (M = 28.9, SD = 13.0). PHQ-9 scores at baseline (n = 20, M = 13.3, SD = 5.4) and posttreatment (M = 7.1, SD = 6.7) were statistically significant (p < .002), as was the difference between baseline (n = 17, M = 12.9, SD = 5.4) and 3-month follow up (M = 5.7, SD = 6.1, p < .001). Scores on the BAI showed a medium effect size (Cohen’s d = 0.56) between baseline (n = 20, M = 18.1, SD = 10.6) and posttreatment (M = 8.12, SD = 9.0), and a large effect size (Cohen’s d = 1.01) between baseline (n = 17, M = 18.1, SD = 10.6) and 3-month follow up (M = 8.12, SD = 9.0). One limitation of this study was the large dropout rate between the intent to treat group (n = 42) and the participants who completed treatment (n = 20).

VRET With Veterans In their study comparing VRET with present-centered ther- apy (PCT), Ready et al. (2010) recruited clients currently in treatment at the Atlanta VA Medical Center’s Mental Health Clinic (n = 11, VRET n = 6, PCT n = 5), with one participant from each group dropping out. The clinician who inter- viewed participants was a licensed clinical psychologist with several years of experience working with this population and was blind to participant assignment. Clinicians used the Structured Clinical Interview for DSM-IV, the CAPS, and the Beck Depression Inventory as measures. PCT as the comparison group included psychoeducation about PTSD, problem-solving techniques, and a focus on the “here and now” problems clients experience. Both the VRET and PCT groups experienced improvement in symptoms; however, the authors report “there was not statistically significant improvement in CAPS or BDI scores when individual treat- ment conditions were isolated” (Ready et al., 2010, p. 52). The authors state that the small sample size impeded sig- nificant differences between groups from being found. The VRET group seemed to have lower baseline CAPS scores (M = 87.83, SD = 15.43) than the PCT group (M = 101.00, SD = 9.51). This is likely an artifact of the random assign- ment procedure used with a small sample. The authors cal- culated effect sizes for the mean change in the CAPS and BDI scores for each group. The mean change in CAPS scores for the VRET treatment group yielded a small Cohen’s d of 0.28 from pretest to posttest (n = 5, M = 31.8, SD = 39.1) and a medium Cohen’s d of 0.56 from pretest to follow up (n = 5, M = 25.0, SD = 28.1). Differences in the mean improvement of BDI scores did not yield significant results. It is unclear why the authors chose to combine the

treatment groups and use a dependent samples t test to com- pare changes in CAPS scores on the entire sample between baseline, post-treatment, and follow up. An independent samples t test of the same data for the VRET group at baseline (n = 5, M = 101.0, SD = 9.51), posttreatment (n = 4, M = 75.5, SD = 22.22), and follow up (n = 5, M = 87.00, SD = 6.32), compared to the PCT group at baseline (n = 6, M = 87.83, SD = 15.43), posttreatment (n = 5, M = 59.2, SD = 32.24), and follow up (n = 4, M = 64.75, SD = 34.08) did not reveal any statistically significant differences.

Gamito et al. (2010) completed a randomized controlled pilot study comparing VRET (n = 5), imaginal exposure (n = 2), and waiting list control (n = 3) groups with Portuguese war veterans (n = 10) who had fought in Africa between 1963 and 1970. Measures used to assess participants of the VRET group included the CAPS, a structured interview from the DSM-IV, the IES-R, the SCL-90-R, and the BDI. It is unclear why, but the SCL-90-R and BDI were not admin- istered to the imaginal exposure and waiting list groups at baseline or posttreatment. The authors report that BDI scores for the VRET group were significantly lower at posttreat- ment. There were no statistically significant differences between groups at posttreatment on the CAPS. The IES-R scores for the VRET group were reduced, whereas these scores for the imaginal group and the waiting list control group increased, however the differences were not statisti- cally significant. Due to the small sample size, this study was statistically underpowered and therefore inadequate to val- idly compare VRET with imaginal therapy and waiting list groups.

Ready et al. (2006) describe a group of multiple case studies (Rothbaum, 2006; Rothbaum et al., 2001) where Vietnam veterans (n = 14) were treated with VRET. Mean CAPS scores at posttreatment (n = 14, M = 59.64, SD = 17.77), 3-month follow-up (n = 8, M = 55.13, SD = 14.38), and at 6-month follow-up (n = 11, M = 50.91, SD = 17.24) were all statistically significantly different (p < .05) than CAPS scores at baseline (n = 14, M = 72.57, SD = 16.18). Scores on the BDI at posttreatment (n = 14, M = 21.14, SD = 8.18) and at the 6-month follow up (n = 11, M = 18.45, SD = 9.49) were statistically significantly different (p < .05) than at baseline (n = 14, M = 24.86, SD = 9.70). Three-month posttreatment BDI scores (n = 8, M = 24.25, SD = 9.53), however, were not statistically significantly different from baseline BDI scores.

Discussion Studies using VRET report several difficulties. First, the nature of the treatment itself appears to be difficult for vet- erans to either comprehend or trust. It is suspected that the current generation of service members may be reacting more positively to using virtual reality as a method of treat- ing PTSD because they were raised in a generation more familiar with this type of technology. Ready et al. (2010) describe the older veteran population as being tentative

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

Nelson 177

about trusting the technology to actually help with their PTSD symptoms.

Another difficulty in using VRET with a veteran popula- tion is the amount of time that has lapsed between the trau- matic events and the treatment. Authors suspect the larger time lapse, in which participants have worked harder for a longer period of time to suppress their PTSD symptoms, causes participants to have a more difficult time in allowing themselves to relive the traumatic event in the virtual environ- ment. As a reliving of the events multiple times is necessary in exposure therapy, this population has a much more difficult time in succeeding with exposure therapy in general. Though the clinicians explain to participants and their families that an increase in symptoms is likely to occur at the beginning of treatment, veterans seem to see this increase in symptoms as evidence that the treatment is worsening their condition and may cause many to terminate treatment. A qualitative study of clinician perceptions of VRET found clinicians not trained in the use of VRET expressed concerns about the safety of using VRET with veterans, questioning whether the virtual environ- ment would exacerbate the symptoms of veterans (Kramer et al., 2010). However, in their meta-analysis on the use of VRET with anxiety disorders, Powers and Emmelkamp (2008) conducted a meta-regression analysis which showed that an increase in the number of virtual reality treatment ses- sions yielded larger effects sizes. This difficulty in recruiting veterans as participants in trials using VRET has perhaps stunted possible improvements that could be made to treat- ment protocols that would benefit veterans. Case studies determining how VRET can be better tailored specifically to acclimatizing the veteran population to exposure therapy and to virtual reality technology may be necessary. There have also been high dropout rates in studies where participants are active duty service members (McLay et al., 2012), which could be attributed to difficulties in balancing treatment with military duties, the time commitment of treatment sessions (90-120 min twice weekly for 8-12 weeks), and the possibility of transfers to other military bases occurring mid-treatment.

Kramer et al. (2010) also note that the use of virtual real- ity technology as a form of treatment may cause the thera- peutic alliance to suffer as a result. Therapists expressed concern that multitasking conducting therapy and control- ling complex computer software would prevent the develop- ment of an effective therapeutic relationship. Measurement of how VRET can either positively or negatively affect the therapeutic alliance may be useful in understanding how using a virtual environment can affect the usefulness of the relationship between therapist and client.

Overall, the studies in this review found VRET to be ben- eficial to both active duty service members and veterans experiencing combat-related PTSD. Each group has a dif- ferent set of difficulties preventing them from seeking or receiving treatment, which is evidenced by high levels of attri- tion. It may also explain the difficulty in setting up experi- mental trials to test the efficacy of this treatment. Because the use of virtual reality technology is such a specific field,

and because the purchase and training of virtual reality equipment expends both financial and time resources, the use of VRET in order to treat military service members and veterans for PTSD is not likely to spread quickly. While the actual cost of virtual reality technology is becoming less expensive, hesitation in the field over using exposure ther- apy in general, despite its positive results, will likely con- tinue to hinder this form of treatment.

One last area where future studies using VRET may want to focus is the distal impact VRET may have. Treatment pro- viders want to ensure positive treatment results continue over time. It has been suggested that studies follow veterans and service members who have been treated with VRET for up to 2 years in order to measure the distal effects of the treatment (Powers & Emmelkamp, 2008). If positive distal effects of the treatment can be more readily established, the benefits of the treatment would perhaps balance out the dif- ficulties seen in implementing it on a wide-scale basis.

Acknowledgment

The author thanks Dr Bruce Thyer for his assistance in preparing this manuscript for publication.

Declaration of Conflicting Interests

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author received no financial support for the research, author- ship, and/or publication of this article.

References

References marked with an asterisk indicate studies included in the systematic review. The in-text citations to studies selected for sys- tematic review are not preceded by asterisks. American Psychiatric Association. (2000). Diagnostic and statisti-

cal manual of mental disorders (4th ed., text revision). Arlington, VA: American Psychiatric Association.

Casey, G. W. (2011). Comprehensive soldier fitness: A vision for psychological resilience in the U.S. Army. American Psycholo- gist, 66, 1-3.

*Gamito, P., Oliveira, J., Rosa, P., Morais, D., Duarte, N., Oliveira, S., & Saraiva, T. (2010). PTSD elderly war veterans: A clinical controlled pilot study. Cyberpsychology, Behavior, and Social Networking, 13(1), 43-48.

Gerardi, M., Cukor, J., Difede, J., Rizzo, A., & Rothbaum, B. O. (2010). Virtual reality exposure therapy for post-traumatic stress disorder and other anxiety disorders. Current Psychiatry Reports, 12, 298-305.

Kraft, M., Amick, M. M., Barth, J. T., French, L. M., & Lew, H. L. (2010). A review of driving simulator parameters relevant to the Operation Enduring Freedom/Operation Iraqi Freedom veteran population. American Journal of Physical Medicine & Reha- bilitation, 89, 336-344.

Kramer, T. L., Pyne, J. M., Kimbrell, T. A., Savary, P. E., Smith, J. L., & Jegley, S. M. (2010). Clinician perceptions of virtual reality

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .

178 Traumatology 19(3)

to assess and treat returning veterans. Psychiatric Services, 61, 1153-1156.

McLay, R. N., Graap, K., Spira, J., Perlman, K., Johnston, S., Rothbaum, B. O., Difede, J. A., Deal, W., Oliver, D., Baird, A., Bordnick, P. S., Spitalnick, J., Pyne, J. M., & Rizzo, A. (2012). Development and testing of virtual reality exposure therapy for post-traumatic stress disorder in active duty service members who served in Iraq and Afghanistan. Military Medicine, 177(6), 635-642.

*McLay, R. N., Wood, D. P., Webb-Murphy, J. A., Spira, J. L., Wiederhold, M. D., Pyne, J. M., & Wiederhold, B. K. (2011). A randomized, controlled trial of virtual reality-graded exposure therapy for post-traumatic stress disorder in active duty service members with combat-related post-traumatic stress disorder. Cyberpsychology, Behavior, and Social Networking, 14, 223-229.

Powers, M. B., & Emmelkamp, P. M. (2008). Virtual reality expo- sure therapy for anxiety disorders: A meta-analysis. Journal of Anxiety Disorders, 22, 561-569.

Pull, C. B. (2005). Current status of virtual reality exposure therapy in anxiety disorders. Current Opinion in Psychiatry, 18, 7-14.

*Ready, D. J., Gerardi, R. J., Backscheider, A. G., Mascaro, N., & Rothbaum, B. O. (2010). Comparing virtual reality exposure therapy to present-centered therapy with 11 U.S. Vietnam vet- erans with PTSD. Cyberpsychology, Behavior, and Social Net- working, 13(1), 49-54.

*Ready, D. J., Pollack, S., Rothbaum, B. O., & Alarcon, R. O. (2006). Virtual reality exposure for veterans with posttrau- matic stress disorder. Journal of Aggression, Maltreatment & Trauma, 12, 199-220.

Reger, G. M., Gahm, G. A., Rizzo, A. A., Swanson, R., & Duma, S. (2009). Soldier evaluation of the virtual reality Iraq. Telemedi- cine and e-Health, 15(1), 101-104.

*Reger, G. M, Holloway, K. M., Candy, C., Rothbaum, B. O., Difede, J., Rizzo, A. A., & Gahm, G. A. (2011). Effectiveness of virtual reality exposure therapy for active duty soldiers in a military mental health clinic. Journal of Traumatic Stress, 24(1), 93-96.

Riva, G., Raspelli, S., Algeri, D., Pallavicini, F., Gorini, A., Wie- derhold, B. K., & Gaggioli, A. (2010). Interreality in practice: Bridging virtual and real worlds in the treatment of posttrau- matic stress disorders. Cyberpsychology, Behavior, and Social Networking, 13(1), 55-65.

Rizzo, A., Reger, G., Gahm, G., Difede, J., & Rothbaum, B. O. (2009). Virtual reality exposure therapy for combat related PTSD. Post-Traumatic Stress Disorder, 6, 375-399.

Rothbaum, B. O. (2006). Virtual Vietnam: Virtual reality exposure therapy. In M. Roy (Ed.), Novel approaches to the diagnosis and treatment of posttraumatic stress disorder (pp. 205-218). Amsterdam, The Netherlands: IOS Press.

Rothbaum, B. O., Hodges, L. F., Ready, D., Graap, K., & Alarcon, R. D. (2001). Virtual reality exposure therapy for Vietnam veterans with posttraumatic stress disorder. Journal of Clinical Psychia- try, 62, 617-622.

Stetz, M. C., Long, C. P., Wiederhold, B. K., & Turner, D. D. (2008). Combat scenarios and relaxation training to harden medics against stress. Journal of CyberTherapy & Rehabilita- tion, 1, 239-246.

Virtual Iraq Afghanistan Media Story CBC [video file]. Retrieved from http://www.youtube.com/watch?v=Ltl9zbDRZWY& feature=autoplay&list=UUQrbzaW3x9wWoZPl4-l4GSA &playnext=1

Wood, D. P., Murphy, J. A., Center, K. B., Russ, C., McLay, R. N., Reeves, D., . . . Wiederhold, B. K. (2008). Combat related post- traumatic stress disorder: A multiple case report using virtual reality graded exposure therapy with physiological monitoring. In J. Westwood, R. Haluck, H. Hoffman, G. Mogel, R. Phillips, R. Robb, & K. Vosburgh (Eds), Medicine meets virtual reality 16 (pp. 556-561). Fairfax, VA: IOS Press.

Wood, D. P., Murphy, J., McLay, R., Koffman, R., Spira, J., Obrecht, R. E., . . . Wiederhold, B. K. (2009). Cost effectiveness of virtual reality graded exposure therapy with physiological monitoring for the treatment of combat related posttraumatic stress disorder. Studies in Health Technology & Informatics, 144, 223-229.

T hi

s do

cu m

en t i

s co

py ri

gh te

d by

th e

A m

er ic

an P

sy ch

ol og

ic al

A ss

oc ia

tio n

or o

ne o

f i ts

a lli

ed p

ub lis

he rs

. T

hi s

ar tic

le is

in te

nd ed

s ol

el y

fo r t

he p

er so

na l u

se o

f t he

in di

vi du

al u

se r a

nd is

n ot

to b

e di

ss em

in at

ed b

ro ad

ly .