Comparison of Palmtop-Computer-Assisted Brief Cognitive-Behavioral Treatment to Cognitive-Behavioral Treatment for Panic Disorder

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1 Journal of Consulting and Clinical Psychology Copyright 1997 by the American Psychological Association, Inc. 1997, Vol. 65. No. 1, X/97/$3.00 BRIEF REPORTS Comparison of Palmtop-Computer-Assisted Brief Cognitive-Behavioral Treatment to Cognitive-Behavioral Treatment for Panic Disorder Michelle G. Newman Stanford University Justin Kenardy University of Queensland Steve Herman and C. Barr Taylor Stanford University In the present study, the authors sought to determine whether the efficiency and cost-effectiveness of cognitive-behavioral treatment (CBT) for panic disorder could be improved by adjunctive computerassisted therapy. Eighteen participants who met Diagnostic and Statistical Manual of Mental Disorders (3rd ed., revised; American Psychiatric Association, 1987) criteria for panic disorder were randomly assigned to a 12-session CBT (CBT12) condition (D. H. Barlow & M. G. Craske, 1989) or to a 4-session computer-assisted CBT (CBT4-CA) condition. Palmtop computers, with a program developed to incorporate basic principles of CBT, were used by CBT4-CA clients whenever they felt anxious or wanted to practice the therapy techniques and were used by all participants as a momentary assessment tool. CBT4-CA clients carried the computer at all times and continued to use it for 8 weeks after termination of therapy. Analyses of clinically significant change showed superiority of CBT12 at posttest on some measures; however, there were no differences at follow-up. With the rapid emergence of health care management organizations, an examination of the viability of cost-effective psychotherapy approaches is becoming crucial. Such examination is important because we are quickly moving toward a reimbursement system that may restrict the number and type of therapy sessions provided. As noted by Yates (1994), however, only a small number of studies have examined which treatments deliver the optimal outcome for the lowest cost. Research does support a dose-response effect for psychodynamic and interpersonal psychotherapies (e.g., Howard, Kopta, Krause, & Orlinsky, 1986), but few studies have examined the minimum number of cognitive-behavioral sessions required to achieve optimal Michelle G. Newman, Steve Herman, and C. Barr Taylor, Department of Psychiatry and Behavioral Science, School of Medicine, Stanford University; Justin Kenardy, Department of Psychology, University of Queensland, Queensland, Australia. Steve Herman is now at the Department of Psychology, University of Southern Mississippi. This study was supported in part by funds from the National Health and Medical Research Council, Canberra, Australia, and the University of Newcastle Research Management Committee, Newcastle, Australia. We gratefully acknowledge Louis Castonguay and Thomas D. Borkovec for their feedback on an earlier draft of this article. We also thank Michelle Mackintosh for her assistance in the study. Correspondence concerning this article should be addressed to Michelle G. Newman, who is now at the Department of Psychology, The Pennsylvania State University, 310 Moore Building, University Park, Pennsylvania Electronic mall may be sent via Internet to outcome. This study attempted to address this issue by comparing the effectiveness of 12-session cognitive-behavioral therapy (CBT12) to 4-session computer-assisted CBT (CBT4-CA) for panic disorder. Substantial research evidence suggests that the treatment of choice for panic disorder is a cognitive-behavioral intervention that incorporates exposure, cognitive restructuring, and relaxation training. Such a multicomponent approach to panic has been shown to be more effective than singular CBT components (Clum, 1989; Clum, Clum, & Surls, 1993; Michelson & Marchione, 1991 ), supportive therapy approaches (Chambless & Gillis, 1993), pharmacological interventions (Clum et al., 1993), and placebos (Chambless & Gillis, 1993; Clum et al., 1993). Given that multicomponent CBT is the gold standard for treatment of panic disorder, studies are needed to evaluate whether the efficiency and cost-effectiveness of this approach can be improved. Several studies support the efficacy of self-help CBT for panic disorder. These studies show that bibliotherapy alone is as effective as eight sessions of group or individual CBT (Gould, Clum, & Shapiro, 1993; Lidren et al., 1994) and that two selfhelp approaches to exposure are as effective as 3.1 hr of selfexposure instructions from a psychiatrist (Ghosh & Marks, 1987; Ghosh, Marks, & Carr, 1988). Despite preliminary findings demonstrating efficacy of self-help therapy, development of a variety of cost-effective treatment options may be essential to panic sufferers for whom traditional forms of treatment are not available. In addition to improving the cost-effectiveness of CBT, we need to develop ways to ensure that CBT research is effectively 178

2 BRIEF REPOI~S 179 translated to clinical practice. Although CBT is considered a short-term approach, a survey of therapists who use combined CBT packages showed that the average treatment time was 42 hr (qhmer, Beidel, Spaulding, & Brown, 1995). Most research studies, on the other hand, tend to implement combined CBT in about sessions (e.g., Klosko, Barlow, Tassinari, & Cerny, 1990; Michelson et al., 1990). There is also research suggesting that CBT techniques may be underutilized by mental health care providers (Breier, Charney, & Heninger, 1986; Taylor et al., 1989). Thus, methods that increase the dissemination of CBT are needed. Computers have the potential to increase both the cost-effectiveness and dissemination of CBT. Computer programs have been shown to effectively implement such CBT techniques as relaxation (e.g., Baer & Surman, 1985; Buglione, DeVito, & Mulloy, 1990), systematic desensitization (e.g., Buglione et al., 1990; Chandler, Burck, Sampson, & Wray, 1988), self-exposure (e.g., Cart, Ghosh, & Marks, 1988; Ghosh et al., 1988), and cognitive restructuring (Selmi, Klein, Greist, Johnson, & Harris, 1982; Selmi, Klein, Greist, Sorrell, & Erdman, 1990). In addition, computer programs have demonstrated success in the treatment of agoraphobia (e.g., Chandler et al., 1988). The palmtop computer is particularly suited for therapeutic applications. These computers are less expensive (about $500 each) and far more portable than desktop personal computers or laptops, weighing from 11 oz. to 15 oz. ( g to g). As a result, palmtop computers can be used wherever patients go to reinforce the systematic use of cognitive-behavioral procedures, and to help them engage in active coping at all times. Moreover, because CBT is well structured and systematically implemented, it lends itself easily to interactive computer software (Selmi et al., 1990). The computer also has the potential to increase compliance with self-monitoring. Although two studies have examined the use of the palmtop computer in the treatment of obesity (Agras, Taylor, Feldman, Losch, & Burnett, 1990; Burnett, Taylor, & Agras, 1985) no study has examined the use of the palmtop computer as an adjunct to the treatment of panic disorder. Participants Method Participants between the ages of 18 and 65 were recruited through advertisements. Individuals were first screened over the phone and those who met Diagnostic and Statistical Manual of Mental Disorders ( 3rd ed., rev.; DSM-III-R; American Psychiatric Association, 1987) criteria for panic disorder with or without agoraphobia were interviewed a second time using the Structured Clinical Interview for the DSM-II1-R (SCID; Spitzer, Williams, Gibbon, & First, 1989). Those who had a primary diagnosis of panic disorder across both interviews and experienced at least two panic attacks during the week before starting treatment were eligible for the study. Exclusion criteria included unwillingness to either remain on a stable regimen of medication or medication-free during the study, a current diagnosis of substance abuse or dependence, obsessive-compulsive disorder, schizophrenia, bipolar mood disorder, organic brain disorder; or current suicidality. Individuals were also excluded if they had previously received an adequate dosage of CBT for panic disorder. All evaluators were advanced PhD-level students or PhDlevel psychologists experienced in the SCID interview. Of the 20 clients who entered treatment, 18 completed it with 9 clients and 1 dropout per condition. The 18 clients had a mean age of 38 years (SD = 11.7, range, 25-62) with 15 women (83%) and 3 men (17%). The mean duration of panic disorder was 7.5 years (SD = 9.9, range,.33-40). Ten clients (55.6%) had received previous treatment with no success. A one-way analysis of variance (ANOVA) found no difference between the two groups in duration of panic (CBT12: M = 6.11, SD = 7.49; CBT4-CA: M = 8.86, SD = 12.17). Chi-square analyses, X2( 1, N = 18), detected no differences in the number of persons who met criteria for agoraphobia (CBT12 = 8, CBT4-CA = 6), had received previous therapy (CBT12 = 5, CBT4-CA = 5), or who were on anxiety medications (CBT12 =. 2, CBT4-CA = 2). Twelve participants (67%) were recruited through Stanford University, and 6 participants (33%) were recruited through the University of Newcastle, New South Wales, Australia. Participants at both sites were evenly distributed across both treatments. Procedure Participants in both treatments used a Casio PB-1000 palmtop computer which has been used in previous studies as an assessment tool (Kenardy, Fried, Kraemer, & Taylor, 1992; Taylor, Fried, & Kenardy, 1990). The PB-1000 has a small keyboard, a touch-sensitive screen, and weighs 15 oz. ( g). A complete report detailing each participant's computer interactions was printed out and reviewed during office visits. In CBT12 the computer served only a self-monitoring function, whereas in CBT4-CA it contained a therapy component. Because detailed information on the computer program is published elsewhere (Newman, Kenardy, & Taylor, 1996) it is only described briefly here. The computer program contained two modes: diary only and treatment plus diary. The diary only mode prompted the person at 9 p.m. to report their average level of anxiety and how many panic attacks they had that day. In this mode, solely for self-monitoring purposes, clients had no access to therapy aspects of the program. The treatment-plus-diary mode combined the 9:00 p.m. prompt of the diary-only mode with additional self-monitoring and therapy components. It is initiated in one of two ways: (a) The client switches on the computer and (b) the computer beeps the client at 8:00 a.m., 12:00 p.m., 4:00 p.m., and 8:00 p.m. This mode contains three modules: (a) Selfstatement and exposure module, (b) symptom control module, and (c) postpanic module. The self-statement and exposure module displays a series of self-statements and suggestions to help the clients alter their thinking and remain in the present situation. The symptom control module prompts clients to practice breathing retraining to achieve an optimal breathing rate. The postpanic module is a computer-initiated program that beeps clients 30 min after each computer interaction. This module presents a sequence of self-reinforcing and reevaluation statements to help clients objectively reassess their fears. Treatment Conditions Treatment was conducted either at the Stanford University School of Medicine or the University of Newcastle, New South Wales, Australia. CBT12 treatment. CBT12 took place over 12 weekly 1-hr individual sessions, and therapists closely adhered to a detailed treatment manual (Craske, Rapee, & Barlow, 1987). Clients were assigned homework and weekly readings from a workbook (Barlow & Craske, 1989). This treatment included cognitive restructuring, breathing retraining, progressive muscle relaxation, exposure to interoceptive cues, and exposure to feared situations. Clients used the computer in the diary only mode to make end-of-the-day ratings of their average anxiety level and number of panic attacks. CBT4-CA treatment. CBT4-CA took place over four weekly individual sessions (6 hr) with the first two sessions lasting 2 hr. Clients used the computer in the diary-only mode during baseline and began using

3 180 BRIEF REPORTS the treatment-plus-diary mode after the first therapy session. After the fourth therapy session, clients continued using the computer in the treatment-plus-diary mode for 8 weeks. In this way, CBT4-CA clients made use of the computer therapy program for the same amount of time the CBT12 clients were in treatment (12 weeks). At Week 13 (posttest assessment), the computer was taken away. Therapists closely adhered to an abbreviated version of the Craske et al. (1987) manual rewritten for four sessions. Clients were assigned homework and weekly readings from a very brief workbook written to inform clients on therapeutic uses of the computer. Homework included use of the computer (a) to monitor thoughts, beliefs, and sensations for all anxiety episodes and panic attacks and (b) to monitor dally anxiety. The computer was also used to practice and prompt the use of breathing retraining and cognitive restructuring, as well as to track evidence for inaccurate predictions. This treatment included cognitive restructuring, breathing retraining, exposure to interoceptive cues, and exposure to feared situations. Therapists All 6 participating therapists had extensive experience in the use of CBT techniques. They were advanced PhD-level students, PhD-level psychologists, or psychiatrists, and they administered both treatments to an equal number of participants. Measures At baseline assessment, clients were given a written description of their assigned treatment, after which they completed a two-item measure of treatment credibility. At posttreatment clients completed a similar three-item treatment satisfaction measure. Items rated on a 5-point scale from not at all ( 1 ) to extremely (5) were summed to form a total score. Measures administered at three assessment points included the Fear Questionnaire Total Phobia Rating and Agoraphobia subscale (Marks & Mathews, 1979), the Mobility Inventory for Agoraphobia (MI; Chambless, Caputo, Jasin, Gracely & Williams, 1985), the Agoraphobic Cognitions Questionnaire (ACQ) and the Body Sensations Questionnaire (BSQ; Chambless, Gallagher, & Bright, 1985). Clients were also asked at each assessment point to identify the number of panic attacks they had during the previous week. Results Because this was an exploratory study of the effectiveness of a new treatment technique and we wanted to reduce the likelihood of a Type II error, we chose not to lower the required alpha rate. Treatment Credibility and Satisfaction An initial one-way ANOVA, conducted to rule out threats to internal validity with respect to treatment credibility, detected no significant differences. The CBT12 and CBT4-CA treatments reported a similarly high credibility rating (CBT12: M = 8.00, SD = 1.41; CBT4-CA: M = 7.56, SD = 0.38). A univariate analysis also detected no differences between the two treatments in level of posttreatment satisfaction (CBT12: M = 12.75, SD = 0.75; CBT4-CA: M = 12.75, SD = 0.62). Statistical Significance of Treatment Outcomes Outcome measures were arranged into three conceptually consistent groups for the purpose of multivariate analyses: (a) Overall fear and panic sensations (i.e., number of panic attacks, BSQ, and Fear Questionnaire), (b) behavioral avoidance (i.e., MI Accompanied and Alone subscales), and (c) panic cognitions (i.e., ACQ). Multivariate analyses of variance (MANOVAs) comparing baselines showed significant differences between the two treatments on behavioral avoidance, F(2, 15) = 5.61, p <.05. Subsequent univariate ANOVAs indicated a difference in the MI Alone subscale, F( 1, 16) = 5.5, p <.05, suggesting greater baseline avoidance in CBT12 (M = 3.61, SD = 0.71) than in CBT4-CA (M = 2.64, SD = 1.03). No other baseline differences were detected. A repeated measures analysis of covariance (ANCOVA) with baseline as the covariate detected no differential effect of treatment condition on the two MI subscales. Results of a 2 (Condition) 3 (Assessment Time) mixed MANOVA showed neither main effects of Condition nor Condition Assessment Time interactions for conceptual groups. Thus, there was no evidence of differential effectiveness of CBT12 and CBT4-CA. l Multivariate main effects of time were found for fear and panic (Table 1 ), F(8, 54) = 9.85, p <.0005; behavioral avoidance, F(4, 62) = 10.51, p <.0005; and panic-related cognitions, F(2, 15) = 6.02, p <.05. Subsequent univariate analyses revealed significant effects of time for all measures (see Table 1 and Figure 1 ) supporting a positive effect of both treatments on all major panic symptoms. Clinical Significance of Treatment Outcomes Although both treatments resulted in nomothetically significant improvements, evaluation of the clinical significance of these changes provides further support of treatment effect. Norms and test-retest reliability estimations of measures were drawn from prior publications (e.g., Chambless, Gallagher, & Bright, 1985; Chambless, Caputo, et al., 1985; Michelson & Mavissakalian, 1983 ). For change on the Panic Attack measure to be clinically significant, the client had to be experiencing no panic attacks at posttest or follow-up. On the basis of recommendations of Jacobson and Truax (1991), the Reliable Change Index (RCI) and Functional Recovery (FR) were calculated. Only clients who met both criteria were considered to have met clinical significance. Clients were considered to have reliably deteriorated if their score remained in the range of the dysfunctional population and their degree of change from pretest or posttest exceeded measurement error. Table 2 presents percentages and numbers of clients who met conjoint criteria at posttest and follow-up for each treatment group. Chi-square analyses of percentage of individuals meeting criteria showed superiority of CBT12 at posttest on number of panic attacks, XZ( 1, N = 18) = 4.0, p <.05; and the BSQ, XZ(1, N = 18) = 4.0, p <.05. However, at follow-up, there were no longer any differences detected between the two treatments. There were also no differences between the treatments at posttest or follow-up in reliable deterioration.,. 1 Preliminary repeated measures MANOVAs that included treatment site and diagnosis (panic disorder with or without agoraphobia) as between-subjects factors found no main effects of treatment site or diagnosis and no interactions among site, diagnosis, condition, and time.

4 BRIEF REPORTS 181 Table 1 Means (and Standard Deviations) by Treatment Condition Over Time M (and SD) for: Measure and condition Baseline Posttest Follow-up dfs F ratios for time effects Behavioral avoidance MI Accompanied subscale CBT (0.92) 1.44 (0.39) 1.47 (0.57) CBT4-CA 2.39 (0.93) 1.73 (0.89) 1.83 (0.95) Alone subscale CBT (0.71) 1.91 (0.82) 2.01 (0.98) CBT4-CA 2.64 (1.03) 1.82 (0.89) 2.01 (1.01) Panic-related cognitions ACQ CBT (9.11) (9.46) (7.86) CBT4-CA (10.68) (6.14) (7.10) Overall fear and panic symptoms Panic attacks CBT (3.92) 0.22 (0.67) 0.44 (0.73) CBT4-CA 6.11 (3.52) 1.56 (2.07) 0.38 (0.74) Fear Questionnaire Agoraphobia subscale CBT (7.95) (6.71) (9.40) CBT4-CA (10.99) 7.56 (8.75) 8.00 (8.17) Total Phobia Rating CBT (19.02) (12.63) (19.61) CBT4-CA (22.24) (23.23) (24.34) BSQ CBT (9.18) (15.67) (13.25) CBT4-CA (11.06) (12.90) (12.33) 2, "* 2, ** 2, "* 2, ** 2, ** 2, ** 2, "* Note. MI = Mobility Inventory for Agoraphobia; CBT12 = 12-session cognitive-behavioral treatment; CBT4-CA = 4-session computer-assisted cognitive-behavioral treatment; ACQ = Agoraphobic Cognitions Questionnaire; BSQ = Body Sensations Questionnaire. ** p < Discussion This study compared the effectiveness of CBT12 with that of CBT4-CA for panic disorder. Statistical analyses detected significant effects of both treatments at posttest and follow-up with no between-treatment differences. Analyses of clinically significant change showed superiority of CBT12 at posttest; however, these differences disappeared at follow-up. Averaging across all follow-up measures, 46% of CBT12 and 35% of CBT4-CA demonstrated clinically significant improvement. Both treatments eliminated the presence of panic attacks, typically regarded as the core feature of panic disorder, in 67% of the clients. This compares favorably to other exposure-based studies for which the average clinically significant improvement is less than one third of clients (Jacobson, Wilson, & Tupper, 1988). Consistent with previous findings (e.g., Agras et al., 1990; Burnett, Taylor, & Agras, 1985), the computer therapy was acceptable to clients. Pretreatment ratings showed that clients found CBT4-CA to be as credible as CBT12. In addition, CBT4- CA was associated with equal ratings of posttreatment satisfaction and equally low dropout rates. One potential risk of treating clients with a tool that gives them continuous access to therapy is client dependency. We tested this possibility by removing access to the computer after 13 weeks. If such dependency had developed, it is likely that significant deterioration would have been noted between posttest and follow-up. However, there were no differences between the two treatments in levels of deterioration and both groups continued to maintain treatment gains at 6-month follow-up. This finding is particularly relevant to the cost-effectiveness of ambulatory computer treatment. Such a finding suggests that palmtops could be purchased by therapists and loaned to clients on a short-term basis. An estimation of costs per client based on an average fee for service of $80 per therapist contact hour, palmtop computer hardware costs, base station costs, and miscellaneous costs can be approximated to be $900 for CBT4-CA and $1,440 for CBT12. If we assume that both treatments are equally effective then CBT4-CA costs $540 less than CBT12. Using the same estimations, CBT4 without the computer is $800 per person, about $100 less than CBT4-CA. Thus, the use of the palmtop does not excessively increment the cost of brief therapy. In addition to being cost-effective, palmtop computers pro-

5 182 BRIEF REPORTS vide other advantages to the cognitive-behavioral therapist. Cognitive-behavioral treatments require regular client selfmonitoring. Daily self-monitoring allows the therapist to track the client's progress. Despite its importance, clients often have problems complying with self-monitoring requirements and either forget to note important information or wait until the evening before their therapy session to note events from the previous week. The latter may result in retrospective memory biases. The palmtop computer creates an incentive to note important events by beeping clients at regular intervals and by providing therapy prompts to help them through difficult episodes. In addition, the computer has an internal clock that records the date and time of each self-monitoring incident thereby allowing the therapist to determine whether regular self-monitoring is being conducted. Another keystone of CBT is regular practice of cognitivebehavioral skills. The regular practice and application of cognitive-behavioral strategies helps clients replace old habitual responses that had exacerbated anxiety and panic with new skills that reduce anxiety. Moreover, the application of newly learned skills helps demonstrate the efficacy of these skills to the client. However, panic-disordered clients often report that when they are confronted with an acute anxiety episode, they forget what they were supposed to do to reduce their panic. The ambulatory computer reminds clients how to reduce their anxiety by leading them through breathing retraining and cognitive restructuring strategies. Limitations of this study must be considered in interpreting the findings. First, this study contains a small sample size with 9 clients in each group. It is possible that with a larger number of clients, some differences may have been detected between the two treatments. A second limitation is the failure to include a comparison condition involving brief (four session) therapy without a palmtop computer. Our failure to include such a comparison group constrains us from drawing conclusions as to Table 2 Clients Meeting Conjoint Criteria for Clinically Significant Change No. of clients Rel. Rel. Measure and condition Posttest deter. Follow-up deter. No. of panic attacks CBT12 89 (8)* 0 67 (6) 0 CBT4-CA 44 (4)* 0 67 (6) 0 MI Alone subscale CBT12 44 (4) 0 33 (3) 0 CBT4-CA 33 (3) 0 22 (2) 1 Accompanied subscale CBT12 0 (0) 0 22 (2) 0 CBT4-CA 11 (1) 0 11 (1) 0 Fear Questionnaire Total Phobia Rating CBT12 78 (7) 0 67 (6) 0 CBT4-CA 44 (4) 0 56 (5) 0 Agoraphobia subscale CBT12 56 (5) 0 56 (5) 0 CBT4-CA 33 (3) 0 44 (4) 0 ACQ CBT12 22 (2) 0 22 (2) 0 CBT4-CA 22 (2) 0 22 (2) 0 BSQ CBT12 89 (8)* 0 56 (5) 1 CBT4-CA 44 (4)* 0 22 (2) 1 Note. Conjoint criteria represents the percentage of individuals who reliably improved (reliable change index > 1.96) and whose mean placed them closer to the mean of the functional population than the mean of the dysfunctional population. Rel. deter. = number of individuals who reliably deteriorated; MI = Mobility Inventory for Agoraphobia; CBT12 = 12-session cognitive-behavioral treatment; CBT4-CA = 4-session computer-assisted cognitive-behavioral treatment; ACQ = Agoraphobic Cognitions Questionnaire; BSQ = Body Sensations Questionnaire. * p <.05. 6" c~.~ 5, "~ 4 O 3" 2: 2" 1- Pre-treatment Post-treatment Followup whether the palmtop computer program provided any benefit beyond the abbreviated therapy. In addition, this study lacks treatment and nonspecific control groups. We decided against a control group because of the substantial support for the effectiveness of CBT for panic disorder (see Chambless & Gillis, 1993; Clum et al., 1993; Michelson & Marchione, 1991 ). Moreover, CBT12 had effect sizes that compare very favorably to other controlled treatment studies. Using pretest measures as a comparison, the effect size was 1.7 at posttest and 1.6 at followup. This is above the average effect size of 1.18 for behavior therapies at posttest (Clum et al., 1993) and 0.9 reported by Shear, Pilkonis, Cloitre, and Leon (1994) for PCT at follow-up. Future research should replicate and extend the present results using a larger sample size and include a comparison to brief therapy without the computer. Such a study using an expanded computer program that includes an exposure module is currently being conducted. Figure 1. Number of panic attacks at three assessment periods. Open squares represent 12-session cognitive-behavioral treatment (CBT12); closed circles represent 4-session computer-assisted cognitive-behavioral treatment (CBT4-CA). References Agras, W. S., Taylor, C. B., Feldman, D. E., Losch, M., & Burnett, K. E (1990). Developing computer-assisted therapy for the treatment of obesity. Behavior Therapy, 21,

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