The Use of Homework in Behavior Therapy for Anxiety Disorders

The Use of Homework in Behavior Therapy for Anxiety Disorders
[Special Issue: Integration of Between-Session (Homework) Activities into Psychotherapy]
Huppert, Jonathan D.1,2; Ledley, Deborah Roth1; Foa, Edna B.1
Section Editor(s): KAZANTZIS, NIKOLAOS; RONAN, KEVIN R.
1Department of Psychiatry, University of Pennsylvania.
2Correspondence concerning this article should be addressed to Jonathan Huppert, CTSA at University of Pennsylvania, 3535 Market St., 6th Floor, Philadelphia, PA 19109. E-mail: huppert@mail.med.upenn.edu
Abstract
In this article, the authors discuss the role of homework in behavior therapy for the anxiety disorders. First, the authors describe the essential components of behavior therapy that include exposure to feared consequences and cessation of all avoidance behaviors. Then, the authors briefly review the literature on the relationship between homework compliance and treatment outcome. Next, the authors discuss the way that homework is used in terms of self-monitoring and exposure exercises during the course of treatment. Finally, the authors discuss the practicalities of encouraging homework compliance and managing noncompliance.
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Behavior therapy is an empirically based treatment approach that has demonstrated efficacy across the anxiety disorders (see Hersen & Bellack, 1999, for discussions of behavior therapy in panic disorder, obsessive–compulsive disorder, social phobia and posttraumatic stress disorder, or for specific treatment manuals including suggestions for homework assignments see Oxford University Press/Graywind Publications manuals). In addition to the empirical stance taken by researchers of behavior therapy, clinicians and patients are also encouraged to take the stance of scientists in the context of treatment. Specifically, treatment involves testing beliefs that they have about particular situations during treatment sessions and on their own through the use of homework assignments.
Behavior therapy for the anxiety disorders focuses primarily on having patients confront situations that that they are avoiding. Avoidance can be overt (e.g., a person with social phobia who refuses to do any public speaking) or more subtle (e.g., speaking softly in order to prevent the audience from noticing possible imperfections). These subtle avoidance strategies are often called safety behaviors. Safety behaviors are strategies used by patients with anxiety disorders to attempt to prevent harm or other negative consequences, such as carrying a bottle of pills in order to prevent having a panic attack or not participating in conversations so people cannot evaluate him or her negatively. A related concept is the use of rituals in obsessive–compulsive disorder (OCD). Rituals are behaviors or mental actions meant to decrease the anxiety experienced in response to obsessions. For example, a patient who fears germs and contamination will wash his hands carefully after being out in public in order to avoid contracting an illness. While avoidance can seem helpful to patients in the short-term because it alleviates anxiety, avoidance has long-term consequences of maintaining anxiety by preventing the patient from learning that the feared consequences of confronting situations are unlikely to occur. Furthermore, avoidance prevents patients from learning that if they remain in the anxiety-provoking situation without the use of safety behaviors or rituals then anxiety will decrease. Therefore, the essential components of treating anxiety are exposure to feared stimuli and cessation of all safety behaviors, rituals, and overt avoidance.
Three types of exposure exercises are used in the treatment of anxiety disorders: In vivo, imaginal, and interoceptive exposures. Homework usually includes repeating the exposures that were conducted in session or conducting variations of them. In vivo exposure entails systematic and gradual confrontation of external situations, places, or activities that trigger fear. The exact nature of in vivo exposures depends on the patient's particular concerns. For example, consider a patient with OCD who has fears about germs. The exposure would be most effective if the patient touched numerous things in the hospital (e.g., door handles, phones, shaking hands with medical personnel, etc.) and then refrained from washing his hands for a period of time once he got home. This exercise would help the patient see that his anxiety would decrease without engaging in rituals and would show him that visiting the hospital does not inevitably cause illness.
Imaginal exposure involves the patient vividly imagining a feared situation and its consequences and, as with in vivo exposure, not avoiding or escaping the resulting anxiety. Imaginal exposure can be used in the treatment of any of the anxiety disorders, but is most frequently used in the treatment of patients with posttraumatic stress disorder (PTSD). In treatment for PTSD, patients are asked to repeatedly recount the trauma that they experienced in order to learn that while the traumatic event itself was dangerous, the memory of the event is not dangerous or harmful.
Finally, interoceptive exposure (also called symptom induction) is a technique that involves having patients confront feared physical symptoms of anxiety (see Craske & Barlow, 2000). The technique is used most frequently in the treatment of panic disorder, which is characterized by a fear of physical symptoms. If patients fear cardiovascular symptoms, for example, interoceptive exposure exercises might include having a patient run on the spot or breathe through a narrow straw for a few minutes. These exercises help patients see that while these symptoms may be uncomfortable, they are not dangerous and are not associated with catastrophic outcomes like heart attacks, fainting, or death.
Although exposure is often characterized as a behavioral technique, it would be inaccurate to assume that cognitions are ignored in behavior therapy. Discussion about likelihood and consequences of anticipated harm or other costs often takes place before, during, and/or after the exposure exercises to in order to promote disconfirmation of erroneous beliefs. Often, cognitive techniques are used to challenge irrational beliefs, particularly if such beliefs are holding patients back from doing exposures.
WHAT DOES THE LITERATURE TELL US ABOUT HOMEWORK COMPLIANCE?
Before discussing how homework is used in behavior therapy, it is important to point out that homework compliance is related to treatment outcome in the anxiety disorders and, therefore, an important component of any treatment program. The available results of this literature consistently demonstrate that compliance with homework is a good predictor of treatment outcome (see meta-analysis by Kazantzis, Deane, & Ronan, 2000, which includes studies of patients with anxiety disorders). The relationship between compliance and outcome has been shown in the treatment of specific phobias (Al-Kubaisy et al., 1992), panic disorder/agoraphobia (Al-Kubaisy et al., 1992; Edelman & Chambless, 1993; Schmidt & Woolaway-Bickel, 2000), social phobia (Al-Kubaisy et al., 1992; Leung & Heimberg, 1996), and OCD (De Araujo, Ito, & Marks, 1996). While homework is an important part of treatment for PTSD (see Foa & Rothbaum, 1998), the relationship between homework compliance and treatment outcome has not yet been examined in this disorder. Vaughan and Tarrier (1992) found that self-directed imaginal exposure to trauma memories was related to anxiety reduction both at the time of the exposure and between sessions, suggesting that homework likely plays an important role in treatment outcome for PTSD. Homework compliance is yet to explored as a predictor of outcome in the treatment of generalized anxiety disorder.
It is interesting that homework compliance has been associated not only with good outcome immediately posttreatment, but also with outcome up to two years posttreatment (Park et al., 2001). In one study examining treatment of patients with social phobia, homework had little effect on outcome posttreatment, but effects emerged at 6-month follow-up: patients who were compliant with homework showed less distress and avoidance than those who were noncompliant (Edelman & Chambless, 1995).
TYPES OF HOMEWORK ASSIGNMENTS
Early Assignments
Homework is a part of the treatment from the first session and, as such, it helps demonstrate the integral role that homework plays in behavior therapy. The rationale for other aspects of the treatment is described in more detail below. Furthermore, assigning homework early encourages a tone of collaborative empiricism in which therapist and patient are working together to understand and treat the disorder. Patients can be given handouts to read about their disorder and the behavior therapy approach to treatment or asked to review recordings of sessions to consolidate what they have learned (e.g., Foa & Rothbaum, 1998).
Early homework assignments should also involve monitoring, in which clients are asked to keep records of the cognitions and behaviors that are related to their core problems. Monitoring helps the patient and the therapist to get a clearer sense of the nature of the problem. This can be especially useful with patients who find it very difficult to report on their symptoms, particularly when the symptoms are very habitual or when they pervade much of patient's day. Self-monitoring also assists patients in seeing how the concepts discussed in session depict reality of their life. This is an excellent way for the therapist to know that the patient understands the treatment rationale. For example, in behavior therapy for OCD, early sessions involve explaining to patients the role that rituals play in the maintenance of obsessions. After patients learn about this functional relationship, self-monitoring often helps to illuminate the importance of this in their own lives. A patient came in stating that she had not been aware of the connection between her obsessions and her compulsions, but that every time she washed, she had a thought about contamination. Sometimes the thought of contamination was triggered by another thought, and she did not realize that she did not need a contaminant immediately in front of her to trigger the obsession that led to the compulsion. An additional example can be seen in a patient who had panic disorder and had not realized she had been carrying money to use to call a cab and escape until she started logging her activities and avoidance.
Clinicians should be aware that self-monitoring can be anxiety provoking to anxious patients. This is not seen as a drawback, but a natural process of the treatment because exposure to anxiety is encouraged throughout the treatment. By monitoring their anxiety, many anxious patients are focusing on their anxiety for the first time, instead of their usual attempts at avoiding thinking about it. This focus can be anxiety provoking and is an excellent introduction to the concept of exposure. Monitoring can be anxiety-provoking anxiety if patients believe that they must complete it perfectly. Perfectionism is quite common across the anxiety disorders and can manifest in various ways (Antony, Purdon, Huta, & Swinson, 1998). For example, socially anxious patients might worry that if they do not complete the homework correctly, the therapist will judge them negatively. Patients with OCD might need their monitoring to be written perfectly or might get anxious about recording just the “right” thing. In such situations, therapists may build doing homework incorrectly on purpose into the hierarchy. Therapist's normalizing of errors made in homework during early sessions is important for all patients and especially useful for those who are more perfectionistic. Regardless, the two important concepts to remember about the first posthomework session is to positively reinforce what has been completed and to assist the patient in seeing how the homework will be used to their own advantage.
Assigning Exposure Exercises for Homework
Once patients have a clear understanding of the theoretical basis underlying behavior therapy, exposure therapy can begin. Because exposures are the most important methods for treating the anxiety disorders with behavior therapy, homework assignments becomes particularly important at this point. There are various reasons why in-session exposures are not sufficient for successful treatment and these reasons should be communicated clearly to patients. By presenting a rationale for the assignment of homework, patients will be much more likely to comply with assignments.
First, in order to maximize treatment effects, patients need more exposure to their fears than they will get in a weekly (or even biweekly) therapy session. Patients often need to have repeated experiences in order to form new beliefs about a given situation. For example, after going to the supermarket alone once, the patient that we described earlier was still quite convinced that she would have a panic attack and faint in this situation. Her subsequent homework assignment was to go to the store alone every day for a week. By the end of the week, she was quite convinced that she could manage in that situation, even if she did feel slightly anxious.
Another reason for having patients do homework is that the patients can view the presence of the therapist, as well as the clinic, as safe, leading them to discount the outcome of in-session exposures and thus continue to avoid feared situations outside of sessions. These safety beliefs can take on many forms. For example, patients with social phobia might discount successful in-session exposures, believing that therapists or office staff will be very gentle with them since they are aware of the patients' concerns. Another patient that we treated with panic disorder had no problem running in place in the therapist's office during interoceptive exposure, but refused to do the exposures at home and continued to avoid exercise as he had for the past five years. When asked what the difference was, the patient responded, “Well, you are here, and I am in a medical center. If anything happens to me, I am sure I will get help quickly.” This helped the therapist design the homework assignment of running in place or conducting other exercises in settings where help was not available (e.g., doing the exercises when no one else was home, going out for a run around the block without taking the cell phone). Patients need to learn that they could also manage in the “real world” without these safety measures in place. These real world experiences often do much more for raising patients' feelings of self-efficacy than do in-session experiences.
Finally, a goal of behavior therapy is to teach patients to be their own therapists. The intent is for patients to learn how to deal with their anxiety on their own so that they can maintain their treatment gains long after active treatment has ended. Homework provides opportunities for patients to start getting used to this role.
THE SPECIFICS OF HOMEWORK
Designing Homework Assignments
As already noted, most homework assignments in behavior therapy for anxiety disorders involve exposure. Frequently, exposures are conducted in a hierarchical fashion, with moderately difficult areas being covered first followed by more difficult areas. The specific situations to be covered are discussed with the patient and selected balancing the importance of confronting anxiety with the patient's willingness to stay engaged in the exposure. Depending on the exposure, the duration, location, frequency for doing the exposures should be discussed. Frequently, for perfectionistic patients, less direction is given in order to create more ambiguity and tolerance for uncertainty.
Often, the first context for an exposure exercise is in the therapy session. The therapist then assigns the same exposure or a slightly more difficult variant for homework. When designing homework, there are two major considerations: to consolidate the gains the patient has made in session through rehearsal and to assign tasks that cannot be or are better accomplished without the presence of the therapist. The former is accomplished by assigning repetition of in session exposures. The latter is best achieved by tailoring the exposures to increase anxiety in a variety of situations throughout the patient's life. For example, a patient with generalized social anxiety disorder may rehearse expressing dissenting opinions with the therapist and other people during a therapy session. For homework, the patient will be assigned to make sure that they express at least three dissenting opinions daily. The therapist would then assist the patient in identifying opportunities in her daily life that she could use for homework. In addition to opportunities that already may exist, the therapist will often assign the patient to create novel situations, such as buying an item from a store and then saying that they are not satisfied with it, in order to assure that the assignment can be done.
Earlier in treatment, we often recommend that patients focus on assigned exposures. Later in treatment, however, patients should start to seize every opportunity for exposure exercises that naturally occur. This helps the patient obtain naturally occurring environmental reinforcers, thereby increasing the generalization of adaptive skills. For example, a panic patient had four sessions of behavior therapy when he was driving in traffic and suddenly felt a panic attack coming on. He quickly turned off the highway and onto the back roads, as he had been doing for years. However, he then recalled the treatment rationale and the need to confront his anxiety (though we had not assigned driving in traffic as homework), and he turned off the back roads, drove back to where he had left the highway, and started waiting in the traffic. When patients take advantage of such opportunities, it indicates strong motivation and good comprehension of the treatment rationale, facilitating the goal of them becoming their own behavior therapists.
Encouraging Homework Compliance
In introducing the general concept of homework, the metaphor of learning a language can be used and may facilitate compliance. For example, patients can be told: “Learning to treat your anxiety is like learning a new language. Did you take a second language in school? What language was it? How did you do? Can you speak it now? If so, what factors led to you retaining it? What makes one fluent in a language? What is a sign that you are fluent?” Each of these questions are discussed in a way that engages the patient. We lead them to the idea that “fluency” can be best demonstrated by being able to argue and dream in a language. Only constant practice can lead to such fluency. In fact, the best way to learn a language is to get some of the basics and then to immerse oneself completely in that language: if one wants to become fluent in French, go to France. We finish the metaphor by pointing out that basically we are going to work on learning a new language: anxiety management. This language is tough to learn, and requires immersion. In sessions, we will work on the basics: the grammar and the vocabulary. The good news is that this is the easy part, there is one major principal in this language: exposure to one's anxiety. The other side of that coin is to stop any avoidance behaviors that one has been engaging in that interfere with exposure. We will be doing a number of things in session to help the patient learn this, and the more that the patient applies what we do at home, the better off he or she will be.
When assigning specific homework assignments, compliance can be facilitated both by the way that homework is assigned and the way in which it is integrated into the subsequent treatment session (see Bryant, Simons, & Thase, 1999). With respect to the way that homework is assigned, where possible, it should be relevant to patients' long-term goals for how they want to live their lives. After homework is assigned, it is also essential that it be reviewed carefully at the beginning of the next session, showing that it was important and meaningful. In our clinical experience, one of the best predictors of noncompliance in homework is not using or reviewing homework in the early sessions of treatment.
Barriers to Completion of Homework Assignments
Homework noncompliance can take many forms and can end up being a major treatment issue. We will address four common types of noncompliance that occur when assigning exposure assignments to patients with anxiety disorders. The first is misunderstanding the homework assignment. The second is outright refusal to do homework. The third is repeated explaining why homework wasn't completed. The fourth is partial compliance with homework. We will briefly discuss the principles of addressing each of these areas followed by a case example.
When a patient does not complete their homework, it is important to be open to multiple interpretations of such behavior. As behavior therapists, we do not assume the patient is being resistant or passive aggressive. One of the best ways of assuming a neutral stance is by determining whether the patient understood what you assigned to them, and, if they did not, to take some responsibility for not having been clearer. After determining what the patient did understand, the therapist can then reexplain the assignment and role-play it to try to ensure the patient understands the assignment and the rationale for the assignment. Having the patient repeat what the assignment is and having them demonstrate what they will do during the assignment can help decrease misunderstanding. For example, a PTSD patient comes in after their first imaginal exposure homework assignment stating that she did not feel anything when listening to the tape and that she had done some in vivo exposure to walking around downtown, an area she had been avoiding. The therapist inquired about how long the patient listened to the tape and what she was doing while listening to the tape. The patient responded that she had listened to the tape while doing her in vivo exposures and while driving to and from work. She thought she was supposed to expose herself to her thoughts and images wherever she had been having them prior to treatment. The therapist apologized for not having been more careful in her explanation of how to do imaginal exposure. Then, the therapist explained that the patient should be in a quiet place where she will not be interrupted for an extended period of time. The rationale for imaginal exposure was reviewed, and the patient completed the homework more accurately. At the next session, the patient reported having felt engaged in the imaginal exposure and had habituated to the less intense parts of the tape.
Patients may refuse to complete a homework assignment for a number of different reasons. The three most common reasons are misunderstanding of the assignment, progressing up the hierarchy too quickly, and overvalued ideation. We addressed misunderstanding above. If a patient reports that he cannot complete the homework, there is no use in pushing to get the patient to agree. Even if they give in and agree, they are very unlikely to follow through when they are alone. Therefore, in addition to explaining the rationale for the assignment, the therapist works with the patient to achieve a compromise. For example, a patient with OCD with contamination concerns conducted an in session exposure of putting paper from the office trash on her clothes and body. However, she was not willing to take the paper home and contaminate her home. She said she understood that she should do it, but would feel too overwhelmed, even though she had been able to conduct the exposure in the office. In the end, she agreed to leave the paper in the car the first day, then to bring it to one area of the house that was already deemed contaminated. Bringing the paper to the rest of the house did not happen for homework, but during a therapist visit to the house.
There are times when patients with anxiety disorders hold on to their beliefs about the consequences of confronting their feared object that they appear close to delusional. Such beliefs have been labeled as overvalued ideation in OCD (see Kozak & Foa, 1994) and can be predictors of poorer outcome in OCD. If a patient refuses to engage in an exposure for homework because they believe it will truly be harmful, more emphasis is made about in session exposures, modeling the exposure, and challenging the patient's motivation for change. For such patients, as is the case for many homework issues, the noncompliance is a reflection of a greater therapy issue that needs to be addressed carefully in session. For example, a patient concerned about getting AIDS from touching the doorknob of a bathroom reluctantly engaged in the exposure with the therapist's guidance. However, when assigned for homework, the patient refused. Further exploration led the therapist to realize that the patient believed that the doors the therapist selected must have been safe because the therapist would not put the patient in harm's way. However, he believed that most bathrooms are in fact contaminated and would lead to AIDS if he touched the doorknobs. The therapist had the patient randomly pick five bathrooms throughout the area and then the therapist went with the patient to the bathrooms, modeling exposures and having the patient engage in them. The patient was then more willing to engage in the exposures for homework.
If a patient repeatedly gives reasons for not doing their homework, this should be considered carefully so as to give the patient the benefit of the doubt while still helping the patient see that it is a problem. The conversation ultimately ends up being about choice and motivation for change. A patient with social phobia came in stating that he had not conducted any of the homework exercises assigned to him regarding speaking with strangers. The therapist asked what prevented him from doing them. The patient said that he worked late every night and was too tired. The therapist acknowledged that it is hard to find time to do exposures when one works extremely hard. Then the therapist said,”So, it must be hardworking so much that you don't have any time for yourself. Did you do anything outside of work this week?“The patient replied that he had gone to a movie alone, had watched a football game on TV, and had read a book. The therapist then asked the patient how he might have been able to incorporate the homework assignment into his busy workday and his pleasure activities. After the patient came up with a few ideas, the therapist complimented the patient for his creative thinking and suggested that the more the patient could do such problem solving independently, the more likely the patient would be to improve. The patient said he understood and completed a large proportion of his homework over the next few sessions.
Partial completion of homework is very common among patients with anxiety disorders. Some patients will only complete the monitoring and easier parts of exposures; some will not complete monitoring at all; and others may engage in their exposures, but continue to conduct their avoidance behaviors or compulsions, or vice versa. Partial compliance can be due to a combination of the above factors (misunderstanding, lack of motivation, anxiety, etc.). It is important to reinforce the part of the homework that was completed and then to carefully understand the factors that led to the lack of completion of the rest of the assignment. For example, one patient reported completing all of his exposures but continuously refused to complete any monitoring of his symptoms or assignments. English was his second language and completing the forms was difficult for him, even in his native language. However, he also had difficulties with not doing things perfectly and was not sure he could complete his monitoring forms correctly. The intervention was to have the patient imperfectly complete the forms, which did not lead to anxiety. The therapist therefore determined not to push the completion of forms and emphasized the completion of exposures, and the patient improved significantly. Another patient reported completing all of her exposures to contaminants in his hierarchy, but was not habituating. A careful analysis by the therapist determined that the patient was continuing to engage in mental rituals immediately after engaging in the exposure. This led to maintenance of anxiety between sessions. After reviewing the rationale for ritual prevention, the patient was asked to do an exposure in session and refrain from all safety behaviors. The patient noticed that this exposure felt different than when she had tried it previously, and habituation occurred between homework exercises once she dropped all of her rituals.
CONCLUSION
Our clinical experience and the data from the research that exists suggest that homework compliance can be an important factor in determining behavioral treatment outcome for the anxiety disorders. Homework compliance is representative of motivation for change and comprehension of the treatment rationale, and it helps the patient generalize and consolidate gains made in treatment sessions. As in all other aspects of treatment, flexibility must be used to shape the homework to the individual patient's needs and stage of treatment.
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