Cultivation of Mindfulness and Acceptance Processes in ACT and CBT: A Randomized Clinical Trial in a Pure Self Help Context
Andrew N. Orayfig
University at Albany, State University of New York
There is a paucity of research on self-help approaches within Acceptance and Commitment Therapy (ACT); specifically there is a need for more randomized controlled trials to elucidate the effectiveness of ACT-based biblio-therapy relative to more traditional cognitive behavior therapy (CBT). The aim of the present research, therefore, is two-fold: (a) to provide a preliminary comparison of ACT and CBT for anxiety in a self-help context and (b) to examine how the two treatments impact ACT-relevant processes in an international community sample (N=200) of persons reporting difficulties with anxiety and fear. Participants were randomized to receive either an ACT or CBT workbook, and five process variables relevant to ACT were assessed at pre- and post- intervention periods twelve weeks apart (i.e., self-compassion, mindfulness, psychological flexibility, thought suppression, and cognitive fusion/defusion). Results are reported here for participants who completed both pre- and post- intervention assessments (N=67). Consistent with expectations, ACT and CBT moved all five ACT processes in expected directions; however, in all cases, ACT did so to a significantly greater extent than CBT. These results have implications for the effective delivery of ACT and CBT biblio-therapy to the general population, especially to areas where dissemination of efficacious treatment is limited.
Cultivation of Mindfulness and Acceptance Processes in ACT and CBT: A Randomized Clinical Trial in a Pure Self Help Context
The etiology of pathological anxiety is complex and multifaceted. Over the last five decades, several important advances in the understanding of anxiety and its treatment have led to the evolution of novel therapeutic paradigms emerging from three distinct waves of behavioral and cognitive therapies. The first wave focused on behavioral methods, while the second wave added cognitive methods, thus leading to the widely known term, cognitive behavior therapy (CBT). The most recent wave involves a focus on mindfulness and acceptance processes, and utilizes a range of strategies that target the function of anxious feelings and thoughts rather than altering the form of those thoughts. This third wave encompasses several new therapies and a growing evidence base (see Hayes, 2004, for a review of the three waves). The third-wave model attempts to resolve some of the differences between behavioral and cognitive process explanations while integrating mindfulness and acceptance approaches. This model is exemplified by Acceptance and Commitment Therapy (ACT; Hayes, Luoma, Bond, Masuda & Lillis, 2006).
ACT is a clinical program based on a detailed theoretical account of human language and cognition known as Relational Frame Theory (RFT; see Blackledge, 2003, for a review). Specifically, ACT claims that psychological inflexibility is a primary source of psychopathology. This inflexibility is proposed to stem from a history of weak control over contextual language processes (Hayes, Luoma, Bond, Masuda & Lillis, 2006). Individuals with such a history often attempt to directly manipulate the form and frequency of negatively evaluated thoughts and emotions, a process which tends to amplify painful content and limit behavioral options in the service of valued life directions (Hayes, Luoma, Bond, Masuda & Lillis, 2006).
Within the ACT model, psychopathology and treatment are broken down into six core processes that lead to psychological inflexibility and suffering, as well as six targets of therapeutic intervention with the goal of promoting psychological flexibility (Figure 1). The first inflexibility process addressed in ACT is cognitive fusion, which is defined as “excessive or improper regulation of behavior by verbal processes” (Hayes et al., 2006, p. 6). In other words, the possibility for valued action becomes limited because individuals treat their thoughts and emotions as literal rather than verbal, thus limiting their behavioral options (e.g. the thought, “life is hopeless”, is treated as being equivalent to a hopeless life). Consequently, the corresponding ACT intervention target is called cognitive defusion, which focuses on changing the function of private events (rather than their form or frequency) by creating new contexts in which to relate to them. For instance, clients are often instructed to repeat a troublesome thought continually until only its sound is left with the goal of reducing the literal qualities and believability of the thought (Hayes et al., 2006).
The second inflexibility process is experiential avoidance, which is defined as “the attempt to alter the form, frequency or situational sensitivity of private events even when doing so causes behavioral harm” (Hayes et al., 2006, p. 7). It is addressed within ACT through the change process known as experiential acceptance, which is an active awareness and acceptance of internal events without attempting to change their form or frequency. Together, the change processes of cognitive defusion and experiential acceptance both fall within the general intervention goal of fostering mindfulness and acceptance (Hayes et al., 2006).
The third and fourth inflexibility processes – dominance of the conceptualized past/feared future and attachment to the conceptualized self – are similar as well in that they both describe views of the self that tend to limit the possibility for valued action in the present moment. They involve constant rumination and self-blame concerning the past coupled with crippling anxiety concerning the future and a self-image that is inextricably linked to rigid and inflexible narratives. These processes serve to keep individuals stuck in their own minds and unable to fully experience the present moment and what the situation may afford in terms of values. The corresponding intervention targets are known as present moment contact and self as context, and they both serve to address these issues (Hayes et al., 2006).
Finally, the last two inflexibility processes are a lack of values clarity and inaction/impulsivity/avoidant persistence. For example, individuals may concern themselves so excessively with avoiding psychological pain that this becomes their immediate goal. In the process, long-term values (e.g. relational intimacy, spirituality, or physical health) become less clear and behavioral patterns begin to center around avoiding psychological distress rather than pursuit of values. These two processes are addressed in ACT intervention through a focus on values clarity and committed action, both of which attempt to help individuals choose valued life directions to pursue and set goals in service of those values (Hayes et al., 2006). Overall, the ACT intervention targets closely parallel the proposed processes of psychopathology.
Although it is often easier to examine core processes of psychopathology and positive change within their respective treatment models, it is crucial that each component process of the models also be examined independently. Recent work on the impact of mindfulness, acceptance and defusion processes in predicting levels of anxiety and willingness to experience discomfort have confirmed that these processes are intrinsically useful skills that can be developed autonomously from ACT treatment (Hayes et al., 2006). In general, results have shown good support for the positive impact of these processes (Hayes et al., 2006). Some examples include the use of acceptance and defusion to predict pain tolerance (Hayes et al., 2006), the use of defusion in reducing the discomfort and believability of negative self-thoughts (Hayes et al., 2006), and the use of acceptance to predict panicogenic reactions to a carbon dioxide challenge (Hayes et al., 2006). In addition to the above work, values-based processes are beginning to be tested as well (Hayes et al., 2006).
Importantly, lower levels of these skills are shown to be related to higher levels of emotional, cognitive and behavioral dysfunction (Dalgeish, Yiend, Schweizer & Dunn, 2009; Kashdan, Barrios, Forsyth & Steger, 2006; Kelly & Forsyth, 2009). For example, one study showed that thought suppression of disturbing emotions paradoxically increases negative mood in individuals with clinical baseline levels of negative mood compared to low negative affect individuals (Dalgeish et al., 2009). The authors suggested that emotional thought suppression (similar to emotional avoidance) is a mechanism for maintaining high levels of depression or anxiety and that other methods such as acceptance would be more useful in clinical populations (Dalgeish et al., 2009). Other studies have found experiential avoidance (EA) to be related to several correlates of psychopathology in anxious individuals. For example, individuals with higher EA levels showed maladaptive emotional coping strategies as well as higher levels of anxiety-related pathology. They also showed significant disruptions in healthy, pleasant and spontaneous life activities relative to individuals with lower EA (Kashdan et al., 2006). EA and anxiety sensitivity levels in an undergraduate female sample also predicted physiological and self-report responses to a fear-inducing laboratory procedure (Kelly & Forsyth, 2009). It is apparent that the processes of psychopathology and change that are targeted in ACT treatment can be observed and manipulated independently from the complete treatment package.
Although preliminary, mindfulness- and acceptance- based treatments have shown great success so far as clinical interventions for a wide variety of problems. The use of Mindfulness Based Stress Reduction (MBSR), for example, has been shown to be effective in treatment of adolescent psychiatric populations (Biegel, Brown, Shapiro & Schubert, 2009). In a randomized clinical trial of MBSR for adolescents, MBSR + treatment as usual (TAU) patients showed significant improvement over TAU-only patients in self-esteem, interpersonal sensitivity, trait and state anxiety, various symptoms of psychopathology, perceived stress, Axis I diagnoses, and Axis V global assessment of functioning scores (Biegel et al., 2009). Similarly, a proposed model of an Acceptance-Based Behavior Therapy (ABBT) for treatment of Generalized Anxiety Disorder (GAD) has shown success in both an open trial (Roemer & Orsillo, 2007) and a randomized controlled trial (Roemer, Orsillo & Salters-Pedneault, 2008). The model proposed by Roemer and colleagues recognizes ABBT component processes such as experiential avoidance and lack of values as crucial components in the etiology and maintenance of pathological anxiety. Although the results are preliminary, the model was able to detect positive changes not only in treatment outcomes (GAD scores, depression and anxiety scores, etc.) but also in acceptance and mindfulness processes. Thus, not only can the proposed mechanisms of change be examined outside a defined treatment package (see above), but these processes can also be measured as part of treatment, which is a crucial step in determining the usefulness of ACT.
ACT as a complete treatment package has been shown to effect positive change over a wide array of psychological problems. Hayes and colleagues (2006) have presented a thorough compilation of the early ACT outcome literature, and they report average between condition effect sizes for ACT of d=.66 at post and follow up periods. These data compare ACT outcomes across a diversity of problem areas including diabetes, substance abuse, anxiety, smoking, depression, chronic pain, and epilepsy, among several others. It is important to note that ACT does not target the alleviation of symptoms per se, but instead seeks to change how people relate with their private experiences (i.e. thoughts, emotions and memories) in the hopes of helping individuals move toward a more valued life with whatever they might think or feel. As a result, ACT outcome studies tend to focus on evaluation of private experiences such as reducing self-stigma in substance abuse (Luoma, Kohlenberg, Hayes, Bunting, & Rye, 2008) and increasing willingness to experience obsessions in Obsessive-Compulsive Disorder (Twohig, Hayes, & Masuda, 2006).
One area wherein the ACT model has had particular success in explaining and treating psychopathology is with anxiety disorders. For example, Dalrymple and Herbert (2007) have adapted the ACT model for treatment of generalized Social Anxiety Disorder (SAD). The authors note the lack of consistency in CBT process studies and suggest that the processes of change in ACT make it a good model for treatment of SAD and anxiety in general. The authors implied that cognitive fusion, experiential avoidance and a lack of values clarity play key roles in the maintenance of SAD; they suggested that ACT intervention targets have the potential to increase acceptance of anxiety in exposure therapy as well as functioning and quality of life across several domains. Nineteen participants underwent a twelve-week program combining ACT and exposure therapy. Participants showed improvements in outcomes, processes and quality of life, relative to a 4 week baseline period, with large effect sizes (Dalrymple & Herbert, 2007). Importantly, earlier changes in process measures predicted later changes in symptoms. Dalrymple and Herbert (2007) incorporated an ACT for anxiety twelve-week treatment plan that has become standard in both classic therapeutic settings (e.g. Eifert, Forsyth, Arch, Espejo, Keller & Langer, 2009) and in manualized/self-help contexts (e.g. Forsyth & Eifert, 2007; Sheppard & Forsyth, manuscript under preparation). Eifert and colleagues (2009), for instance, report the positive results of three case studies extending the usefulness of this twelve-week plan to include individuals suffering from obsessive compulsive disorder, panic disorder and social phobia. As mentioned previously, Twohig, Hayes, and Masuda (2006) also implemented ACT as a treatment for OCD, and participants showed clinically significant reductions in compulsions as well as an increasing willingness to experience obsessions without engaging in cognitive fusion. As a final example, a randomized controlled effectiveness trial of ACT for anxiety and depression (Forman, Herbert, Moitra, Yeomans & Geller, 2007) found that ACT was at least as effective as CT in an outpatient setting, although results were preliminary. Overall, ACT has flexibility in effecting change across a variety of anxiety disorders (Eifert et al., 2009). This suggests a common underlying etiology in line with the ACT psychopathology model (Eifert et al., 2009).
In light of these early successes of the ACT for anxiety model, it is important to consider processes of change within ACT and CBT. Specifically, it is necessary to consider both common and unique mechanisms of change between the two models in hope of gaining a more complete understanding of pathological anxiety. In a comparison of ACT and CBT, Hofmann and Asmundson (2008) make the claim that the “third wave” treatment approach is not new and simply represents an extension of current cognitive-behavioral methods. The authors state that values work and behavior change processes are fully compatible with current behavioral models, while acceptance, mindfulness and defusion processes simply target response-focused emotional coping (rather than antecedent focused coping in CBT). This emphasis on similarities over differences is explored further in another comparison of ACT and CBT in the treatment of anxiety disorders (Arch & Craske, 2008). Arch and Craske (2008) suggest that dichotomous conceptions of outcomes (i.e., symptom reduction versus valued living), treatment of thoughts (i.e., cognitive restructuring versus defusion) and treatment of emotions (i.e., prediction/control versus acceptance) may be overly simplistic. They note that both therapeutic models may, in fact, work through similar processes (e.g., mastery and control over anxiety symptoms and thoughts) and may lead to similar outcomes (e.g., symptom reduction in the service of living out one’s values). They note that the mediation literature is too young to make definitive causal statements about processes of change. Overall, the comparative literature suggests that the processes of change in ACT and CBT, when examined independently from their respective therapeutic paradigms, may in fact be overlapping to some degree. This tentative conclusion must be taken into consideration if differences and similarities between the two waves will be elucidated.
It is clear that the content of treatment for pathological anxiety (i.e., ACT vs. traditional CBT) is a complex issue that is not easily resolved. In addition, the mode of treatment delivery is an equally important question. Specifically, it is important to address whether self-help and manualized treatments, in addition to Internet-based treatments, can effect positive change in processes and outcomes similar to changes seen in traditional psychotherapy. The use of behavioral biblio-therapy is not a new treatment option. Glasgow and Rosen (1978) have reviewed some of the complex issues involved in designing, utilizing, and evaluating behavioral self-help workbooks. Some of the design issues found to be of general concern included the question of single- versus multi-component workbook designs and the question of self- administered, minimal contact, or therapist-administered utilization. The authors also stress the importance of reducing attrition and conducting systematic follow-up evaluations in order to clarify treatment utility, explain behavior change, and measure maintenance of therapeutic gains. Evaluation of workbook utility and measurement of therapeutic gains are especially important considering the large amount of resources expended by the public on popular self-help books. In a more recent review of popular biblio-therapy, Redding, Herbert, Forman and Gaudiano (2008) describe biblio-therapy as a multi-million dollar per year industry that is popular for a wide range of mental health problems. In light of the benefits of self-help biblio-therapy in terms of autonomy and cost-effectiveness the authors systematically rated fifty popular self-help books for anxiety, depression and trauma for their scientific grounding, usefulness and possible harmful effects. Overall, the authors report that the most highly rated books tended to have PhD level professors and mental health professionals as first authors, adopted a cognitive behavioral perspective, and focused on specific problems.
The use of self-administered treatment (SAT) for emotional disorders is well-documented. For example, Hecker and colleagues (Hecker, Losee, Fritzler & Fink, 1996; Hecker, Losee, Roberson-Nay, & Maki, 2004) have designed and evaluated a manualized self-help treatment for Panic Disorder (PD). In a preliminary trial, the authors found no differences in outcomes between self-directed and therapist-directed manual use. In addition 40% of self-directed participants and 28.6% of therapist-directed participants achieved clinically significant gains at a six-month follow up (Hecker et al., 1996). In a later study by Hecker and colleagues (2004), a group using the PD manual in combination with brief therapist contact performed similarly well when compared to a manual + psychotherapy group (Hecker et al., 2004).
In a recent meta-analysis, Menchola, Arkowitz and Burke (2007) found SAT’s for emotional disorders to be more effective than no treatment controls (NTC; Cohen’s d=1.00), and slightly less effective than therapist administered treatments (TAT; Cohen’s d= – 0.31). The authors conclude that SAT’s are a good adjunct to TAT’s and may be useful where TAT’s are not available. Past meta-analyses (e.g. Den Boer, Wiersma & Van Den Bosch, 2004; Hirai & Clum, 2006) have found similar results, suggesting that self-directed treatments are comparable to therapist-directed treatments and may be useful for treatment of emotional disorders, especially when combined with therapist contact or psychotherapy of some sort. Hirai and Clum (2006) emphasized the use of SAT’s within a stepped-care approach wherein patients that do not respond to preliminary efforts such as SAT’s are given more intensive or personalized care. The authors also briefly discuss a final, emergent mode of SAT delivery – the Internet – as a preliminary but promising venue of treatment.
Very few studies to date have examined the effectiveness of ACT biblio-therapy for the general population. The limited results available, however, are encouraging. Muto, Hayes, and Jeffcoat (in press) compared ACT biblio-therapy to a wait-list group using a sample of Japanese college students studying abroad in the United States. They found that students receiving the book showed significantly better mental health at post and follow-up periods, with results mediated by changes in psychological flexibility. Sheppard and Forsyth (manuscript in preparation) also compared an ACT self-help book for anxiety with a wait-list group. ACT participants showed significant reductions in anxiety-related pathology and also showed significant changes in ACT-relevant process measures, as compared to the wait list group. The potential use of self-help literature as a low-cost and easily disseminated therapeutic option underlies a need for more randomized controlled effectiveness trials for ACT biblio-therapy.
Therefore, the purposes of the present study are twofold: to provide a preliminary comparison of ACT and CBT for anxiety in a pure self-help context and to examine how the two treatments effect changes in ACT processes both similarly and uniquely. Participants were randomized to either an ACT (Mindfulness and Acceptance Workbook for Anxiety; MAWA; Forsyth & Eifert, 2007) or CBT (Cognitive Behavioral Workbook for Anxiety; CBWA; Knaus, 2008) workbook, and were instructed to work with them on their own without therapeutic contact with project staff. These workbooks were structurally similar and they modeled many of the classic techniques and approaches from the two therapeutic approaches. They also met all of the criteria offered by Redding and colleagues (2008) for successful self-help books (i.e. authors were Ph.D.-level mental health experts, cognitive behavioral grounding, and specific problem foci).
This study is part of a larger randomized controlled trial completed through a university-based anxiety research program (Russo & Forsyth, manuscript in preparation). The larger study examined both outcomes and processes, although only process measures are reported here. We anticipated that ACT- and CBT- based bibliotherapy should be distinguishable at the level of target change processes. More specifically, we expected that ACT bibliotherapy would move ACT-relevant change processes (i.e. self-compassion, mindfulness, acceptance, thought suppression, and cognitive defusion) in expected directions to a greater extent than CBT-based bibliotherapy. It is important to note here that a few CBT-relevant processes are described in the larger trial but are not discussed here. The current analyses are limited to ACT-relevant processes in order to assess the unique contributions of ACT bibliotherapy to CBT bibliotherapy. More specifically, the primary question being asked here is not whether ACT or CBT move all processes of change more effectively in anxiety sufferers but whether ACT bibliotherapy adds anything new to traditional CBT bibliotherapy in terms of change processes.
As a central aim of this study was to examine the effectiveness of ACT and CBT as self-help interventions for the general public, an international sample of anxious participants was recruited through Internet-based marketing strategies and through the study website. Inclusion criteria were minimal in order to allow for maximum generalizability. Participants were required to be eighteen years or older, have English reading skills, have Internet access, and report functional impairment and marked distress due to anxiety symptoms (although no formal diagnoses were required). Study candidates who had read either of the self-help workbooks or who expressed suicidal ideation or intent were excluded from the study. Potential participants who completed a demographic assessment and who also met eligibility criteria were subsequently mailed one of the two workbooks. Other than receiving a free workbook, the only notable incentive for participation was the possibility of receiving an Amazon gift card of twenty-five dollars following the assessment at pre-post treatment, and at three and six month follow-up periods.
Demographic information and subsequent analyses are limited only to participants who completed measures at both Time 1 and Time 2 (Original N = 200, CBT condition = 100, ACT condition = 100; Time 2 Completer N = 67, CBT condition = 30, ACT condition = 37). Information gathered from non-completers is described elsewhere (Russo & Forsyth, manuscript in preparation). The majority of completers were female (77.6 %), Caucasian (83.6 %), employed full time (38.8 %), residents of the United States (70.1 %) and had completed college (34.3 % had a graduate education, 28.4 % completed an undergraduate education, and 28.4 % completed some college). Also, most completers were not currently using medication (52.2 %) and were not seeing a mental health professional during the course of the study (61.2 %). Finally, although a previous clinical diagnosis was not a pre-requisite for study participation, the majority of completers reported having been given a diagnosis of an anxiety disorder (53.7%) and/or a depressive disorder (11.9%). Full demographic information can be found in Table 1.
Materials and Measures
Mindfulness and Acceptance Workbook for Anxiety (MAWA; Forsyth & Eifert, 2007). Divided into nineteen chapters and three parts, the MAWA workbook applies ACT to the anxiety disorders. The first part of the book focuses on understanding anxiety and its disorders. This section helps participants gain a clear understanding of their struggles with anxiety and the negative outcomes those struggles have produced in their lives. Also, the core problem of psychological inflexibility is introduced and participants are encouraged to try a new approach. In the second part of the workbook, participants are taught that ending the struggle with anxiety (cultivating psychological flexibility), rather than ending their anxiety, is the solution. They are taught to view their thoughts and emotions through the lens of mindfulness and acceptance rather than self-chastisement and cognitive fusion. Finally, the concept of a value-consistent life is presented as an alternative to anxiety control and management. The third part of the book encourages clarification of values and application of self-compassion to one’s anxiety. This section also includes exposure-like ACT exercises to help increase participants’ willingness to fully experience their anxiety and to move forward with it. Finally, the last few chapters identify barriers that will arise as participants put these practices into action. The book is accompanied by a CD with additional resources and guided meditation exercises.
Cognitive Behavioral Workbook for Anxiety (CBWA; Knaus, 2008). The CBT workbook employed here utilizes classic behavioral and cognitive techniques from Rational Emotive Behavior Therapy (REBT; see Ellis, 1994, for a review). It represents an awareness and action approach wherein participants gain a realistic understanding and awareness of their anxiety, which becomes a catalyst for problem solving. The book is divided into two parts. The first part of the book includes psycho-education on the nature of fear and anxiety, development of self-observant skills, introductory self-management techniques, and the presentation of a multimodal attack against anxiety as well as steps for positive change. The second part of the book introduces more advanced cognitive techniques to build emotional tolerance, quell fear using behavioral methods, break connections between procrastination and fear, stop perfectionism, address self-worth and prevent relapse, among other goals. The emphasis in these approaches is on challenging and changing “parasitic” thoughts and behaviors. The workbook offers several ideas as well as experiential exercises from which participants can choose based on their needs or preferences.
Online Assessment Battery. Participants completed an online assessment battery at both pre- and post- treatment periods. The assessment battery was hosted via Survey Monkey (www.surveymonkey.com). The battery included the following measures.
Self-Compassion Scale (SCS). The SCS (Neff, 2003) is a 26-item measure that assesses the concept of self- compassion, which is defined as “being open to and moved by one’s own suffering, experiencing feelings of caring and kindness toward oneself, taking an understanding, nonjudgmental attitude toward one’s inadequacies and failures, and recognizing that one’s own experience is part of the common human experience” (Neff, 2003, p. 224). The SCS is divided into three subscales: self-kindness vs. self-judgment, common humanity vs. isolation, and mindfulness vs. over-identification. The scale includes questions such as “When things are going badly for me, I see the difficulties as part of life that everyone goes through.” Participants indicate how often they acted in a manner consistent with each of the items using a Likert-type scale of 1=almost never to 5=almost always. The SCS was found to have good internal consistency (.92) and test-retest reliability after a three-week period (.93; Neff, 2003). Furthermore, the scale shows good convergent and discriminant validity, is a good predictor of mental health outcomes, and predicts greater levels of self-compassion in a practicing Buddhist population (Neff, 2003). In the present sample, the SCS was found to have good internal consistency (α=.94).
Mindful Attention Awareness Scale (MAAS). The MAAS (Brown & Ryan, 2003) is a 15-item measure designed to assess the attentional component of mindfulness. Mindfulness is contrasted with mindlessness and is defined by Brown and Ryan (2003) as “the state of being attentive to, and aware of, what is taking place in the present.” The MAAS measures mindfulness indirectly, using mindlessness-endorsing statements such as “I rush through activities without really being attentive to them” and “I find myself preoccupied with the future or the past.” Participants rate their agreement with statements using a Likert-type scale of 1=almost always to 6=almost never. Higher scores indicate less mindlessness and, therefore, greater mindfulness. The MAAS was found to have good test-retest reliability, good convergent and discriminant validity, and is correlated with several different aspects of well-being (Brown & Ryan, 2003). The MAAS was able to predict greater levels of mindfulness in a practicing Buddhist population and was also found to correlate with well-being in a clinical population of breast and prostate cancer patients (Brown & Ryan, 2003). Finally, the MAAS was further validated in a large university sample (Mackillop & Anderson, 2007). In the present sample, the MAAS was found to have good internal consistency (α=.88).
Acceptance and Action Questionnaire (AAQ-9). The AAQ-9 (Hayes et al., 2004) is a 9-item broad measure of psychological flexibility that correlates most closely with the ACT targets of experiential avoidance/acceptance (e.g. “I’m not afraid of my feelings”) and inaction/committed action (e.g. “I am able to take action on a problem even if I am uncertain what is the right thing to do”). The scale is also available in a longer 16- or 22-item version, but the 9-item version was used here for pragmatic reasons. Items are scored on a Likert-type scale of 1=never true to 7=always true, and some items are reverse scored so that higher scores represent greater levels of experiential avoidance. Although results are preliminary and mixed, the AAQ has shown adequate internal consistency (.70) and test-retest reliability (.64; Hayes et al., 2004). The AAQ showed good construct validity when compared to several related process measures (e.g. thought suppression and control, dissociation, and negative coping) and the scale seems to measure a construct above and beyond these processes. In addition the AAQ showed adequate concurrent criterion validity when correlated with several measures of psychopathology and quality of life (Hayes et al., 2004). In the present sample, the AAQ was found to have adequate internal consistency (α=.68).
White Bear Suppression Inventory(WBSI). The WBSI (Wegner & Zanakos, 1994) is a 15-item measure of thought suppression. Thought suppression is generally defined as the conscious avoidance of particular cognitions and is believed to be associated with negative consequences such as obsession and preoccupation with the suppressed thought (Wegner, Schneider, Carter III & White, 1987). As a trait, the concept is related to experiential avoidance and cognitive defusion. Sample items include “There are things I prefer not to think about” and “I often do things to distract myself from my thoughts.” Items are scored on a Likert-type scale of 1=strongly disagree to 5=strongly agree, with higher scores indicating greater levels of thought suppression. The WBSI showed acceptable internal consistency and temporal stability, and good construct validity when correlated with measures of obsessional thinking, depression, anxiety and repression (Wegner & Zanakos, 1994). The scale also predicted signs of clinical obsessions in obsession-prone individuals and predicted depression in individuals prone to suppressing negative thoughts (Wegner & Zanakos, 1994). In another validation study, the WBSI showed good internal consistency and test-retest reliability, in addition to correlating positively with measures of emotional vulnerability and psychopathological symptoms. Finally, subjects with high WBSI scores showed greater amounts of unwanted intrusive thoughts than those with low scores (Muris, Merkelbach, & Horselenberg, 1996). In the present sample, the WBSI was found to have good internal consistency (α=.90).
Believability of Anxious Feelings and Thoughts (BAFT). The BAFT (Forsyth & Eifert, 2008) is a 16-item measure of the perceived validity and believability of anxious thoughts and feelings. The idea of believability/validity is related to the ACT intervention target of cognitive fusion/defusion. Sample anxiety-endorsing statements include “I can’t really do the things that I want to do when I have anxiety and fear” and “It scares me when I can’t keep my mind on a task because it means that something is not right with me.” Items are scored based on their believability on a Likert-type scale of 1=not at all believable to 7=completely believable. The BAFT showed high internal consistency in a healthy undergraduate sample (α=.90) as well as a highly anxious community sample (α=.90). The scale also showed good convergent validity with emotion regulation measures such as experiential avoidance and thought suppression, as well as with anxiety sensitivity (Herzberg, Sheppard & Forsyth, manuscript under review). In the present sample, the BAFT was found to have good internal consistency (α=.87).
Through an Internet-based marketing strategy involving solicitation of anxiety-related websites, study candidates were directed to the study website, which described the study in detail. Potential participants were identified through expressed interest and were then asked via email to complete a SurveyMonkey based assessment containing consent, eligibility, and demographic information. Consenting participants who met all inclusion criteria were then notified via email of their participant status, assigned a study id number, and asked to complete a preliminary assessment battery evaluating ACT process domains as well as several outcome measures described elsewhere (Russo & Forsyth, manuscript in preparation). Participants who successfully completed this assessment were then randomly assigned to receive either the ACT or CBT workbook and were notified via email of their workbook group. Participants were mailed their workbooks in addition to an introductory letter and a proposed twelve week timeline dividing chapters by weeks. In order to increase external validity, participants were reminded that the timeline was a loose guide rather than a rigid schedule.
All participants were assigned a start date two weeks after workbook mailing dates (unless complications in delivery or time constraints were indicated by participants, in which case start dates were modified) and were assigned a workbook completion date twelve weeks after their start date. During this twelve-week period, the researchers only initiated contact with participants to offer reminders to complete three short self-assessments throughout the book (to gauge participation). After twelve weeks, participants were sent a series of reminders to complete a post-workbook assessment battery containing the same measures as the preliminary assessment battery. Participants that successfully completed these two batteries were included in the analyses described here and were entered into a randomized drawing to receive an Amazon gift card. All procedures were approved by a university institutional review board (IRB).
All data were analyzed using SPSS statistical software. First, a series of independent samples t-tests (for continuous variables) and Χ2 analyses (for dichotomous variables) were run on all demographic variables to test for group equivalence at Time 1 between ACT and CBT workbook groups. In addition, a series of univariate analyses of variance (ANOVAs) were run on all process measures to test for group equivalence, as well.
The second set of analyses focused on assessing changes within and between groups over time. A series of repeated measures ANOVAs were run to detect overall significant changes in process measures between Times 1 and 2 as well as to detect significant changes in the interaction of time and group (i.e. whether one workbook group showed significantly greater changes over time in process measures than the other group). Because of the exploratory nature of this study and the relatively small sample size, alpha levels were not corrected to minimize the risk of Type II error (Rothman, 1990). Finally effect sizes were calculated for all between- and within- group differences. Partial eta squared effect sizes were calculated for main effects of time (small effects = .01; medium effects = .06; large effects > .14; Cohen, 1988). Cohen’s d effect sizes were computed at post-treatment for all Time x Group interactions (small effects = .20; medium effects = .50; large effects > .80; Cohen, 1977).
The first group of analyses included a series of t-tests and Χ2 analyses to assess for group equivalence on all demographic variables and process measures at Time 1. All demographic information is reported in Table 1, whereas means and standard deviations of the process measures appear in Table 2. As expected, the two groups were equivalent at Time 1 on all relevant demographic variables (all p’s >.05). In addition to general demographic information, current psychotherapy and current medication use were assessed, although they were not manipulated in order to increase external validity. Importantly, both groups showed equivalence at Time 1 on these two variables (both p’s >.05). Finally, a series of univariate ANOVAs showed that both groups were equivalent at Time 1 for each of the five assessed process measures (all p’s >.05).
A series of repeated measures ANOVAs were then conducted on each process variable to look for significant changes within and between groups over time. The results of these analyses can be found in Table 2. As expected, participants showed noteworthy increases in self-compassion over the twelve week period, as supported by a significant main effect of time, F (1, 66) = 36.50, p < .001, ηp2 = .37 (large effect size). In addition, pre- to post- intervention increases in self-compassion were greater in the ACT relative to the CBT group, as supported by the significant Group x Time interaction, F (1, 66) = 13.50, p < .001, Cohen’s d = .59 (medium effect size).
Participants also showed notable increases in mindfulness over the twelve week period, as supported by a significant main effect on Time, F (1, 66) = 55.40, p < .001, ηp2 = .46 (large effect size). In addition, pre- to post- intervention increases in mindfulness were greater in the ACT relative to the CBT group, as buttressed by a significant Group x Time interaction, F (1, 66) = 8.02, p = .006, Cohen’s d = .60 (medium effect size).
Participants reported substantial decreases in experiential avoidance over the twelve week period, as supported by a significant main effect of time, F (1, 66) = 92.30, p < .001, ηp2 = .59 (large effect size). Moreover, pre- to post- intervention decreases in experiential avoidance were greater in the ACT relative to the CBT group, as supported by the significant Group x Time interaction, F (1, 66) = 4.85, p = .031, Cohen’s d = .55 (medium effect size).
Participants also reported sizable decreases in thought suppression over the twelve week period, supported by a significant Time main effect, F (1, 66) = 26.90, p < .001, ηp2 = .30 (large effect size). Moreover, pre- to post- intervention decreases in thought suppression were greater in the ACT relative to the CBT group as supported by a significant Group x Time interaction, F (1, 66) = 5.40, p = .023, Cohen’s d = .62 (medium effect size).
Finally, participants showed important shifts from fusion to defusion of anxious feelings and thoughts over the twelve week period, as supported by a significant main effect for Time, F (1, 66) = 74.00, p < .001, ηp2 = .54 (large effect size). Furthermore, pre- to post- intervention improvements in defusion were greater in the ACT relative to the CBT group, as supported by a significant Group x Time interaction, F (1, 66) = 6.85, p = .011, Cohen’s d = .53 (medium effect size).
A central aim of this study was to compare the ability of ACT and CBT to move ACT relevant processes in a pure self-help context. To that end, the present findings are encouraging. Within a pure self-help context, both ACT and CBT moved ACT-relevant processes in expected directions, but ACT did so to a larger extent than CBT. These results suggest that ACT self-help can effect change in ACT-relevant processes such as cognitive defusion, acceptance, and mindfulness. In addition, these results are the first to suggest that, although both treatments can move ACT-relevant processes within a self-help context, ACT biblio-therapy can do so to a greater extent than CBT biblio-therapy. These two results have important implications for understanding success and failure in self-help treatment as well as gaining a more complete understanding of the maintenance and treatment of pathological anxiety.
Results showed that both workbooks were able to significantly move all processes in expected directions, and this was a very meaningful outcome as suggested by consistently large main effects of time. This suggests that these processes of change in psychopathology can be learned even when they are not specifically targeted. This idea is in line with the fact that previous randomized trials have shown that ACT works equally as well as cognitive therapy (e.g. Forman et al., 2007) in effecting change in outcomes. If in fact changes in psychological flexibility are an underlying process linked with success in therapy, it may be that successful therapies in general evoke these changes through similar processes, albeit using different terminology or tools to do so (Arch & Craske, 2008; Hofmann & Asmundson, 2008). Hayes et al. (2004) have suggested in their review of behavior therapy that both treatment effects and processes of change in CBT are broader than previous models have allowed. The present research supports a broad conceptualization of therapeutic change processes, though further research is warranted.
The large and significant main effects of time reported here also add to the knowledge base that empirically based self-help literature is an effective form of treatment for anxiety (e.g. Den Boer, Wiersma & Van Den Bosch, 2004; Hirai & Clum, 2006). These data have been analyzed previously for changes in mental health (Russo & Forsyth, manuscript under preparation), and similar positive outcomes have been recorded. It appears from the literature and from the current study that self-help therapy is an effective and low cost tool to reach a wide audience of anxiety sufferers, and that positive effects of treatment extend to processes as well as outcomes.
In addition to showing general improvement, results also showed that participants responded differentially to ACT treatment relative to CBT. Time by group interactions showed that ACT workbook users had significantly greater improvement on all five process variables, and this was accompanied by a consistently medium effect size at post treatment. This suggests that ACT as a treatment package may target these processes of change better than CBT. This may be a result of an increased clarity in the presentation of the psychological flexibility model (Figure 1) in ACT. In other words, ACT participants that are presented with the clear objectives of cultivating acceptance, mindfulness and defusion will tend to do so to a greater degree. However, this does not preclude cultivating such processes within a CBT model, as suggested above. The concept of increased clarity leading to better outcomes is supported by literature suggesting that understanding of these processes can be fostered outside of treatment, and that this understanding leads to a diverse array of health benefits (Hayes, 2004). An increased understanding of the processes may interact, however, with a participant bias whereby participants report greater changes in processes even when such changes are not actually occurring. Although social desirability was not measured here, it seems likely that a desire to change and ‘do well’ in this trial may influence ACT users who understand the processes being targeted. The differential effect of social desirability on ACT and CBT group responses is, however, a concept that is clearly speculative and warrants further research.
The interactive effect of Group x Time also suggests that self-help literature may allow for fine distinctions between different therapies in terms of change processes. The medium effect sizes reported here suggest a certain amount of similarity between the mechanisms of action in the two workbooks. Further research must include more CBT-specific processes to help elucidate real differences between mechanisms of action. Furthermore, any conclusions concerning differential change processes are necessarily limited without complex mediational analyses (Arch & Craske, 2008).
There are a few notable limitations of the self-help and process literature in general, and of this study design in particular, that are worth mentioning. For example, it is still unclear to what extent therapist contact is necessary for treatment success. Although amount of therapist contact is considered an important factor in self-administered treatments (Glasgow & Rosen, 1978), results are mixed. In the present study, the only contact made with participants was in the form of non-therapeutic email reminders and answers to general study questions. It was made clear that no therapeutic advice could be given over the phone or email. It could be that too little contact led to high attrition, which may accurately reflect individuals’ levels of commitment to a self-help book in an external setting, thus supporting the stated goal of external validity. On the other hand, participants’ self-reports seemed to suggest that knowing they would be contacted by study staff about progress (in email reminders) produced significant levels of anxiety and deterred full participation. In addition, some participants were more active than others in participant-initiated email with study staff. All of these factors could confound levels of participation as well as increase attrition. The search for an adequate level of therapist contact should be a goal in future research. Despite these ongoing concerns, however, the present results suggest that therapist contact may not be necessary for participants to benefit from biblio-therapy. This finding is especially important given the need for low-cost, broadly impactful treatments.
Another important limitation of the self-help literature that was elucidated here is the education level necessary to comprehend and effectively utilize the workbooks and exercises. As mentioned previously, 91.1% of workbook completers had at least some college education. In addition, although both workbooks were written at an 8th grade reading level, reasons for attrition given included a lack of understanding of the workbooks and of the exercises outlined therein. Analysis of reasons for attrition and characteristics of non-completers is underway. This research should consider whether completers tend to be more educated than non-completers, and what implications this may have on future workbook design. It has already been suggested that workbook complexity (e.g. single- vs. multi- component designs) is an important consideration (Glasgow & Rosen, 1978), and the present research reinforces this idea. Regardless of these limitations, the use of self-help literature eliminates much of the variation in psychotherapeutic relationships that could confound results, and may thus increase reliability of results.
An important limitation of the process literature is the lack of development of these concepts. Some of these concepts (e.g. values & committed action) are still being operationalized in the literature and clear definitions of the concepts are not yet available. By contrast, evaluations of mindfulness, acceptance and defusion are more robust (Hayes et al., 2006). However, several important questions remain about the utility of these scales. For example, Hayes et al. (2004) caution against using the AAQ to measure change in specific acceptance-based therapies due to its early developmental stage, focus on global concerns and truncated range of scores. These processes have developed out of a specific theoretical and philosophical framework (Hayes et al., 2006) and it is necessary to continue to hone these processes within the concept of psychological flexibility as new results become available. Regardless of this limitation, it is encouraging that converging and overlapping measurements of acceptance, mindfulness and defusion seem to tell a similar story here.
Some final limitations on the current study include a very high attrition rate (66.5%; see Glasgow & Rosen, 1978, for a review of some studies with similarly high attrition rates) and the lack of long term follow up data (analysis currently ongoing) or mediational data. Also, the focus here on a general effectiveness trial may have come at the expense of low efficacy, and future trials will need to find a balance between internal and external validity. In addition, there was no use of a wait-list control group in this trial, which may affect the ability to detect a true baseline at both time points. However, Sheppard and Forsyth (manuscript in preparation) have already examined the Mindfulness and Acceptance Workbook for Anxiety (MAWA; Forsyth & Eifert, 2007) using a wait-list control group. Therefore, the use of only two treatment groups, especially considering the already low n values for each condition, seems justified. Finally, it is possible that a free workbook incentive may have motivated participation but not long-term commitment. Glasgow and Rosen (1978) have suggested that charging a small fee for instructional materials may better approximate the conditions one would find at a local bookstore, and, thus, may lead to better external validity. Therefore, perhaps charging participants a small fee for workbooks may increase external validity while improving long-term commitment because of the monetary investment.
Despite these limitations, the present research provides the first evidence that ACT can move ACT-related change processes more effectively than CBT can move ACT-related processes, even in a self-help context. This has exciting implications for the dissemination of ACT biblio-therapy within a stepped-care approach (Hirai & Clum, 2006). Results such as these suggest that it may be just as useful to provide ACT biblio-therapy in areas where therapist-administered treatment is unavailable (Menchola, Arkowitz and Burke, 2007). Overall, it seems that ACT, to a greater extent than traditional CBT, is able to target and move proposed ACT change processes within a self-help model.
First and foremost, I would like to thank my savior Jesus for the peace and confidence to continue walking through this journey one step at a time, keeping one eye on the truth of scientific discovery and the other on the necessity of human compassion. Without Him, I would truly be lost. I would also like to thank my colleagues in the ADRP lab; I especially thank my supervisor and friend, Amanda Russo – she has constantly given her time unselfishly and enthusiastically throughout this process. I would like to extend an additional thanks to my faculty advisors and readers, Dr. John Forsyth, Dr. Laurie Feldman, and Dr. Sharon Danoff-Burg, for each of their respective comments and criticisms throughout the growing process of this paper. My first plunge into the field of clinical psychology has truly been a group effort, and I am mindful of that.
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The ACT Model of Psychopathology and ACT Targets of Intervention
ACT Model of Psychopathology ACT Targets of Intervention
Figure 1. Hex a Flex Model of ACT Psychopathology and Targets of Intervention. Note that each proposed mechanism of psychological inflexibility as predicted by the third wave model has a corresponding ACT intervention target. From Luoma, J.B., Hayes, S.C., & Walser, R. (2007). Learning ACT: An Acceptance and Commitment Therapy Skills-Training Manual for Therapists. Oakland, CA: New Harbinger and Context Press.
Time 1 Demographic Information for Study Completers