10 Page Psychology Paper
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Obsessive-Compulsive Disorder 1
Running head: COMPARISON OF TWO THERAPY METHODS FOR OCD
Is Cognitive Therapy More Effective than Exposure and Ritual Prevention Treatment
for Adults Diagnosed with Obsessive-Compulsive Disorder?
Fairleigh Dickinson University
Obsessive-Compulsive Disorder 2
Is cognitive therapy more effective than exposure and ritual prevention treatment for adults diagnosed with obsessive-compulsive disorder?
Obsessive-compulsive disorder is classified as an anxiety disorder (DSM-IV-TR, 2006). The obsessions are constant and repetitive thoughts, images or urges that are invasive and inappropriate. These thoughts, images or urges cause severe and debilitating anxiety that the person attempts to disregard, repress or defuse by distracting the thoughts, images or urges with actions. These actions are known as compulsions. The compulsions are carried out mentally or behaviorally. Cognitive compulsions, such as repeating words in silence, counting, and praying are some mental ways of coping with the obsessions. Cognitive compulsions are also known as covert compulsions. Behavioral compulsions such as ordering, checking, hoarding and hand washing are some physical ways to calm the anxiety. Behavioral compulsions, also known as overt compulsions, allay fears caused by the faulty cognitions that create and maintain the overwhelming anxiety associated with Obsessive-compulsive disorder (Rector, Bartha, Katzman, & Richter, 2001).
Although there is no cure for Obsessive-compulsive disorder (OCD) there are different types of treatment that are effective in reducing the anxiety associated with the obsessions and compulsions. Two of the most widely accepted treatments are cognitive therapy and exposure response prevention therapy. Exposure and response prevention therapy (ERP) is a behavior therapy that exposes the client to the objects that are associated with the obsessions that cause the anxiety. This process of exposure
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eventually helps the client feel a reduced amount of stress over time until the feelings of anxiety diminish completely. The primary objective of ERP is to help the client
recognize the obsessions and respond to the anxiety by resisting the urge to act on the compulsions (Rector, et al, 2001).
Cognitive Therapy (CT) observes how a client intellectualizes their obsessions. CT examines how a person considers, understands, and feels about their obsessions. CT also helps a person become aware of how faulty beliefs drive compulsions. The main goals of CT are to help a person recognize obsessive thoughts and their significance. CT therapy examines the validity of the obsessions and cognitive distortions to help the client make positive changes in response toward the obsessions and resist the compulsions associated with the obsessions (Rector, et al, 2001).
CT has been shown to be a very effective form of treatment for OCD. Trained therapists develop a therapeutic alliance with clients to help them identify faulty thoughts and address the compulsions associated with the obsessions. The therapist’s goal is to help clients with OCD overcome the disorder by changing their thinking, behavior, and emotional responses to anxiety (Beck, 1995). Cognitive theorists propose that OCD can be treated more effectively with CT because obsessions and compulsions are generated by cognitive distortions and addressing the thoughts as opposed to the behaviors targets the problem at the root. Also, CT was recommended for clients who did not benefit from ERP therapy due to the initial anxiety provocation which possibly will result in a higher rate of attrition from treatment (McLean, Whittal, Thordarson, Taylor, Scotching, Koch, & Anderson, 2001). One of the most current studies that compared CT and ERP therapy
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found that both methods of treatment were effective, but that CT had slightly higher results at post-test and significant results at follow-up (Belloch, Cabdeo, & Carrio, 2008).
Belloch, et al, (2008) conducted a study (N=29) which compared CT (N=16) and ERP therapy (N=13). Although the sample was small; this study was comprehensive considering approximately 2.5% to 3% of the population was estimated to have OCD. Three measures were used to assess participants at intake. Doctoral psychologists that were experienced in both cognitive and behavioral therapy administered the Anxiety Disorders Interview Schedule (ADIS-IV-L) for DSM-IV lifetime version (Brown, DiNardo, & Barlow,1994), the Yale-Brown Obsession-Compulsion Scale (Y-BOCS), and The Obsessional Beliefs Questionnaire (OBQ), a 44 item self-report questionnaire (Obsessive Compulsive Cognitions Working Group, 2001). The Y-BOCS (Goodman, Price, Rasmussen, & Mazure, Fleishman, Hill, Heninger, & Charney, 1989) was administered again at pre-treatment and determined that the participants (N=29) had severe OCD symptoms with a score of 25.36. This test also found participants were being medicated at a rate of 86.2%. The intake which took 2 to 3 hours was inclusive of drug treatments, physical and mental health history, and demographics.
In addition to the above tests, seven other tests were administered to assess depression, worry, anxiety, negativity, obsessions, strategies, and cognitive distortions. Regardless of scores, the participants were then randomly assigned to CT or ERP therapy with an experienced licensed clinical psychologist. The Y-BOCS was administered after the random assignment at pre-test, again at 3 and 6 months, and then at a 1 year follow-up. The data from the 1 year follow-up was used in this study (Belloch, et al, 2008).
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Both the CT and the ERP therapy followed manual guidelines for treatment. It is important to note that the CT therapy was administered without any behavioral therapy and the ERP therapy was administered without any cognitive module. The ERP treatment was conducted over a 6 month period. In the first six weeks, ten sessions were conducted twice a week for 60-90 minutes. The following ten sessions were conducted bi-monthly for 60-45 minutes. The ERP sessions educated participants about behavioral techniques, developed a hierarchy, introduced exposure tasks, and assigned daily homework. Participants were asked to self monitor their anxiety levels during exposure tasks (Belloch, et al, 2008).
The CT treatment was also conducted over a 6 month period. The participants were introduced to the cognitive components of therapy for OCD and treated for a total of twenty sessions. The first two sessions explained obsessions and compulsions. The next ten sessions were conducted weekly for 60 minutes. These sessions taught participants how to examine their cognitive distortions and learn how to manage the obsessions. The next six sessions were conducted bi-weekly reinforcing the therapy and assigning homework. The last two sessions were introduced to enhance relapse prevention techniques (Belloch, et al, 2008).
This comprehensive study did not exclude participants due to co-morbid findings, current medicine use, or health history. The study compared the results of CT and ERP therapy at pre-treatment, post-treatment, and follow-up to evaluate the effectiveness of
significant improvement for all groups in symptom reduction. Testing concluded that both treatments were successful in treating severe symptoms of OCD. At post–test,
Obsessive-Compulsive Disorder 6 the CT results were shown to be somewhat more successful in reducing the obsessive and compulsive symptoms of OCD. At follow-up, CT was 1 Standard Deviation (SD) higher in reducing the same symptoms than ERP therapy (Belloch, et al, 2008).
Whittal, Robichaud, Thordarson, and McClean (2008) conducted a 2 year follow-up study that examined randomized trials of CT and ERP therapy in both an individual and a group setting. The Y-BOCS did not show significant findings for individual or group participants during the study. However, the Y-BOCS test results for CT were significantly higher than the ERP therapy for individual participants in the follow-up study. Two types of measures, the Obsessional Beliefs Scale (OBQ) and the Interpretations of Intrusions Inventory (III) were conducted. The OBQ consisted of a 44 item self-report measure to test the strengths of the beliefs (Obsessive Compulsive Cognitions Working Group, 2001). The III consisted of a 31 item self-report measure to assess intrusive thoughts (Obsessive Compulsive Cognitions Working Group, 2004). This study also revealed that the drop-out rate was lower for participants who received CT as opposed to participants who received ERP therapy (Whittal, et al, 2008).
Individual participants for this study were assessed at intake with the SCID-I and the Y-BOCS at pre-treatment (N=83), post-treatment (N=59), and follow-up (N=41). The average beginning age for individual participants with OCD symptoms was 23.4 and these participants suffered an average of 13.1years with symptoms. Random assignment of the individual participants (N=75) were (N=37) for CT and (N=38) for ERP therapy. Of the 4 participants that dropped out of CT, 3 had valid grounds. Of the 8 participants that dropped out of ERP therapy, 1 had a possible personality disorder. At the 2-year
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follow-up only 19 of the 37 participants were available for assessment for CT and only 22 of the 38 participants were available for assessment for ERP therapy (Whittal, et al, 2008).
The group participants for this study were assessed and measured in the same manner as the individual participants. The group participants were assessed at intake with the SCID-I and the Y-BOCS at pre-treatment (N=93), post-treatment (N=63) and follow-up (N=45). The average beginning age for group participants with OCD symptoms was 22.5 and the participants suffered an average of 13 years with symptoms. Random assignment of the group participants (N=76) were (N=34) for CT and (N=42) for ERP therapy. Of the 2 participants that dropped out of CT, 1 had a valid reason. Of the 8 participants that dropped out of ERP, 2 had stopped taking medication. At the 2-year follow-up 24 of the 34 participants were available for assessment for CT and 21 of the 42 participants were available for assessment for ERP therapy (Whittal, et al, 2008).
Both group and individual studies were conducted in sequence. One benefit of CT was a significantly lower drop-out rate. This drop-out rate was measured with the Fischer’s exact test and found that the recovery rate for participants in individual CT treatment was significantly higher at the 2 year follow-up than for the participants in the group CT treatment. And, final results showed that individual CT was equally effective and better tolerated when compared to individual ERP therapy treatment (Whittal, et al, 2008). It was supposed that since distorted beliefs and faulty thoughts caused anxiety, CT therapy was a more inclusive treatment than ERP therapy (McLean, et al, 2001). CT
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treatment was recommended for participants who did not benefit from the stress inducing methods of ERP therapy (McLean, et al, 2001) because ERP therapy re-creates anxiety by exposing participants to objects that prompt a fear response (Abramowitz, 2006). However, Abramowitz (2006) examined ERP therapy for OCD and found that ERP therapy had greatly improved the prognosis for treatment of OCD. ERP was seen effective in reducing 50%-60% of symptoms for OCD participants, but post-treatment results indicated participants still had residual symptoms (Abramowitz, 2006).
In comparison studies of CT and ERP therapy, results of the Y-BOCS revealed that after 16 sessions of each treatment CT reduced symptoms by 53% and ERP therapy reduced symptoms by 43% (Abramowitz, 2006). Importantly, Abramowitz (2006) noted that an ERP component was added to the CT therapy at 6 weeks in 2 of the 4 studies and this may have compromised internal validity. Abramowitz (2006) cited Y-BOCS studies that showed the results of CT and ERP therapy were comparable in symptom reduction post-treatment. This result would tend to confirm the findings of Norcross (1995) who stated that neither therapy is exclusively better than another in treatment nor that all therapies work equally well for all psychological disorders.
Although CT results were shown to be comparative in post-treatment the opposite results were reported in follow-up, finding ERP therapy to be more effective. But, 25%-30% failed to finish ERP therapy and 20% of the participants that remained in treatment did not benefit from significant symptom reduction. And, approximately 50%
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of the participants who began ERP therapy did not benefit from treatment. Thus, the incentive to start ERP and/or to remain in therapy was a dilemma for participants because ERP therapy replicated anxiety and was stressful. Consequently, Abramowitz (2006)
suggested therapist training programs to teach better methods of providing and implementing ERP treatment for participants would be beneficial.
The study by McLean, et al, (2001) compared the effectiveness of CT and ERP therapy methods in group treatment. The participants (N=63) who completed the study were between the ages of 18 and 65. Participants were evaluated and assessed for OCD using The Structured-Clinical Interview for DSM-IV (SCID) and the Y-BOCS at 3 different intervals during the treatment. Half of the participants began treatment to establish a baseline and 3 months later the other half of the participants began treatment. Each treatment session was conducted during a 12 week period with 6-8 participants for a total of 2.5 hours (McLean, et al, 2001).
ERP therapists taught participants about OCD characteristics and ERP treatment methods. Initial instructions included the behavioral premises of therapy, demonstrations of self-monitoring and homework assignments. Reinforcement of self-observance and review of homework tasks continued through out the sessions until the participants experienced symptom relief. Relapse prevention skills were emphasized and evaluated during the last therapy session to formulate maintenance strategies (McLean, et al, 2001).
CT therapists taught participants about OCD characteristics and CT treatment methods. CT therapist reviewed 6 faulty thought categories. Each category was addressed and techniques to modify cognitions in a faulty thought category were formulated. Group
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participants examined and reviewed their faulty thought patterns and coping strategies. Homework tasks were specified to formulate maintenance strategies (McLean, et al, 2001). Results of the McLean, et al, (2001) study showed ERP participants had slightly improved symptom management compared to the CT participants at the finish, but findings were not statistically significant. At the 3-month follow-up, ERP participants showed a significant improvement and 55% success rate for symptom management compared to CT participants (Mclean, et al, 2001).
Abramowitz, Franklin, Schwartz, and Furr (2003) examined participants (N=132) who were adult out-patients (70 men, 62 women) between the ages of 18-65. The participants were treated for OCD in 2 different clinical facilities. The participant’s symptoms were categorized using a revised Y-BOCS to examine physical (overt) compulsions and mental (covert) compulsions. The study identified 5 sub-groups of symptoms which included harming, contamination, hoarding, unacceptable thoughts, and symmetry. ERP treatment sessions were 60 to 90 minutes in length and were administered to each of the 5 groups for a total of 15 periods at varying times during a weekly schedule dependent upon the severity of symptoms. Results showed there was a 56.3% decrease in OCD symptoms with the 14% participant attrition rate taken into account (Abramowitz, et al, 2003).
Franklin, Abramowitz, Kozak, Levitt, and Foa, (2000) compared randomized control trials (RCTs) to further determine the effectiveness of ERP treatment for OCD.
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Participants paid a fee for therapy to the Medical College of Pennsylvania-Hahnemann in conjunction with The Center for the Treatment and Study of Anxiety (CTSA) that participated in a continuing National Institute of Mental Health-funded RCT. Participants (N=110) were out-patients adults (58 men, 52 women) between the ages of 17 and 74 who participated in the trial studies that ran over a period of 6 years. A total of 18 comprehensive sessions, the first 3 of which were preparation sessions, were conducted over a 4 week period for 2 hours each (Franklin, et al, 2000).
Participants in this trial were exposed to individual stressors from least feared to most feared. This method of exposure continued until the anxiety gradually decreased. After each session finished, the participants were given different exposure activities and homework tasks. Ritual prevention skills were taught throughout the therapy by using self-awareness and management skills to reduce symptoms. Participants were urged to seek therapist support to discontinue compulsion rituals. Finally, therapists instructed participants in relapse prevention procedures (Franklin, et al, 2000).
Benchmark comparisons of the Y-BOCS were used to assess OCD symptoms. The research cited several meta-analyses with RCTs that indicated ERP was an effective mode of treatment. The main result from this study revealed that symptoms improved significantly from pre-treatment to post-treatment. Of the participants who completed the trial, 86% were seen to have symptom reduction post-treatment (Franklin, et al, 2000).
Results from other meta-analyses in this study showed similar symptom reduction percentages with ranges between 55%, 56.3%, and 60%. Curiously, the RCTs result
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showed a significantly higher result of 86% in symptom reduction. It is important to note that RCTs have been disapproved of by critics because the RCTs lack external validity. It was stated that generalize-ability was difficult because the groups are too homogeneous and participants received a manual type treatment. Alternatively, researchers from this study stated RCTs were externally valid because randomized and non-randomized participants responded to treatment in a like manner. It is important to note this study did not focus on research control and that observances were not strictly monitored (Franklin, et al, 2000).
This hypothesis states that CT is a more inclusive treatment for OCD than ERP therapy because CT targets the distorted core beliefs and faulty thoughts which cause anxiety. CT is also less anxiety provoking than ERP thus having a significantly lower drop-out rate. Several earlier clinical trials have shown ERP therapy to be the treatment of choice for OCD. And, past research has shown that the symptoms associated with OCD declined significantly with ERP treatment (Franklin, et al, 2000). Conversely, cognitive theorists advocate OCD can be treated successfully with CT because this method of therapy targets the causes of OCD (thoughts) and the symptoms (behaviors) in a structured way (McLean, et al, 2001). It is hypothesized that current research literature and future comprehensive research examining comparisons of CT and ERP therapy will illustrate that CT is a more effective treatment than ERP therapy to reduce the obsessive and compulsive symptoms associated with OCD (Belloch, et al, 2008). The following research proposal is submitted to support this hypothesis.
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Participants (N=400) would be recruited during a 1 month time period in January 2010 in the New York Metropolitan area. Morning and evening radio announcements on
1010 WINS and 880 WCBS, Sunday newspaper ads in the local sections of the New York Daily News and the Bergen Record would be placed and an AOL internet website advertisement would invite adult participants (18 – 65 years of age) to area seminars in February 2010 for a free screening and information sessions to learn about OCD. The
seminars would be conducted on different evenings during the week in selected tri-state area mental health offices. The seminar speakers would explain the symptoms of OCD and lecture participants about the procedures and measures to be administered during the free February 2010 screenings. Instructions for the participants would include a summary of the eligibility criteria. This information would be considered a necessary requirement for qualified participants to take part in the free treatment plan that would be conducted for a 3 month period during March, April, and May 2010. Qualified participants would receive one voucher at each session. If participants collect 25 vouchers, one for each session, they would receive a gift certificate for $500.00 at the conclusion of the study. If participants complete the 2 follow-up sessions at the 6 and 12 month intervals, two additional $100.00 gift certificates would be awarded. Compensation for this study would be provided by a grant from the American Psychological Foundation (APF). All participants would be treated in accordance with the “Ethical Principles of Psychologists and Code of Conduct” (American Psychological Association, 1992).
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Qualified participants would be randomly selected and assigned to a group A or a group B. Participants would be randomly assigned to receive either CT or ERP treatment. Participants would be assessed at pre-treatment and during treatment at 4, 8, and 12 weeks. Follow-up assessments would be conducted twice via the telephone at 6 month and 12 month intervals to assess symptom reduction. Results would be compared between groups using 3 measures.
Participants would be administered the (SCID) Structured Clinical Interview (Brown, DiNardo, & Barlow,1994), the (Y-BOCS) Yale-Brown Obsession-Compulsion Scale (Goodman, Price, Rasmussen, & Mazure, Fleishman, Hill, Heninger, & Charney, 1989) and (OBQ) The Obsessional Beliefs Scale (Obsessive Compulsive Cognitions Working Group, 2001), at pre-treatment, at 3 different intervals during treatment and at 2 intervals post-treatment. An information session and symptom history would be obtained from each participant and testing would be administered by the participant’s original intake interviewer at the mental health office where they had attended the assessment seminar. Participants would be randomly assigned to CT or ERP therapy for 12 weeks, 2 times a week for 2 hour sessions each. The use of a familiar clinical setting and interview personnel would be utilized to minimize obsessions and reduce anxiety in an effort to circumvent the high attrition rate normally associated with long term research.
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CT procedures would be outlined by Judith Beck’s (1995) structured model. This CT therapy method would focus on identifying faulty thoughts (obsessions) and employing healthy thoughts to control the repetitive mental and/or physical behavior (compulsions). Homework would be assigned to reinforce and maintain the goals outlined in therapy. ERP procedures would be based on an outpatient program
modeled after the treatment developed by Dr. Edna Foa (1979) and her colleagues at the Center for Treatment and Study of Anxiety (CTSA). This CTSA therapy method would teach complete self-restraint from rituals from the beginning of exposure sessions starting with the least feared object on the hierarchy and eventually working toward the worst feared object by the end of the exposure sessions. Homework is also an essential part of the ERP program and participants would be encouraged to practice assignments on a daily basis. Both the CT and ERP therapy treatments would be conducted for 12 weeks, 2 times a week for 2 hour each session.
Licensed therapists from CTSA with OCD experience and training in both CT and ERP therapy would be recruited to conduct sessions for participants in both groups. There would be 6 therapists for participants in group A and 6 therapists for participants in group B. All sessions would be audio taped and reviewed by supervisors with clinical proficiency in therapy treatments of OCD. Therapists would assess participants at the per-treatment level, at the 4, 8, and 12 week level and later at the 6 month level and the 12 month post-treatment follow-up level.
Obsessive-Compulsive Disorder 16
Three measures would be used to assess the OCD symptoms of the participants. First, participants would be assessed using The Structured-Clinical Interview for DSM-IV (SCID) to confirm the diagnosis of OCD (Brown, DiNardo, & Barlow, 1994). Second, the Yale-Brown Obsession-Compulsion Scale (Y-BOCS) would be administered to participants. The Y-BOCS would measure obsessions and compulsions with a check-list to ascertain frequency, distress, and control of symptoms (Goodman, Price, Rasmussen, & Mazure, Fleishman, Hill, Heninger, & Charney, 1989). Third, a 44 item self-report questionnaire, The Obsessional Beliefs Scale (OBQ) would be administered to assess how the participants rate the relevance of their thoughts in relation to their symptoms of OCD (Obsessive Compulsive Cognitions Working Group, 2001). All these measures would be administered to participants at the pre-treatment level, at the 4, 8, and 12 week level and later at the 6 month level and the12 month level of post-treatment follow-up. It is hypothesized that CT would be shown to have statistically significant results in symptom reduction at all treatment levels and at the post-treatment level and follow-up level as well.
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