IdentifyingEfficacious Treatment Components

of Panic Control Treatment for Adolescents:A Preliminary Examination

Jamie A. MiccoMolly L. Choate-Summers

Jill T. EhrenreichDonna B. PincusSara G. Mattis

ABSTRACT. Panic Control Treatment for Adolescents (PCT-A) is adevelopmentally sensitive and efficacious treatment for adolescentswith panic disorder. The present study is a preliminary examination ofthe relative efficacy of individual treatment components in PCT-A in asample of treatment completers; the study identified when rapid im-provements in panic symptoms occurred over the course of treatmentand which treatment components preceded these gains. Twenty-one ad-olescents (ages 13-17) completed weekly measures of panic-relevantsymptoms, which were examined for between-session gains. Results in-

Jamie A. Micco, PhD, Molly L. Choate-Summers, PhD, Jill T. Ehrenreich, PhD,Donna B. Pincus, PhD, and Sara G. Mattis, PhD, were affiliated with the Center forAnxiety and Related Disorders at Boston University at the time of this study. Dr. Choate-Summers is now at the Pediatric Anxiety Research Clinic at Rhode Island Hospital. Dr.Mattis is now in Private Practice in Winchester, MA.

Address correspondence to: Jamie A. Micco, Massachusetts General Hospital, De-partment of Psychiatry, 15 Parkman Street, ACC 812, Boston, MA 02144 (E-mail:jmicco@partners.org).

This research was made possible by research grant R01 MH58641 from the Na-tional Institute of Mental Health, awarded to the last author.

Portions of this paper were presented at the annual meeting of the Association forthe Advancement of Behavior Therapy in Boston, MA (November, 2003).

Child & Family Behavior Therapy, Vol. 29(4) 2007Available online at http://cfbt.haworthpress.com

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dicate that psychoeducation may precede notable decreases in panic at-tacks while cognitive restructuring may contribute to rapid declines inoverall anxiety and cognitive errors. The authors discuss the importanceof future controlled dismantling studies to examine the relative contribu-tion of PCT-A treatment components. doi:10.1300/J019v29n04_01 [Arti-cle copies available for a fee from The Haworth Document Delivery Service:1-800-HAWORTH. E-mail address: Website: © 2007 by The Haworth Press, Inc. All rightsreserved.]

KEYWORDS. Adolescents, panic disorder, panic control treatment,cognitive behavioral therapy, sudden gains

PREVALENCE AND PHENOMENOLOGY OF PANICIN ADOLESCENT COMMUNITY

AND CLINICAL SAMPLES

The onset of panic disorder, with or without agoraphobia, occursmost often in late adolescence (American Psychiatric Association, 2000),although a number of community and clinical studies have found thatfull-blown panic attacks and situational avoidance are also prevalent inearly to mid-adolescence. While the proportion of adolescents who en-dorse having experienced a panic attack varies across studies, research-ers consistently find that adolescents in the community endorse havinghad panic attacks both with self-report measures and clinical interviews(Hayward, Killen, & Taylor, 1989; Hayward, Killen, & Hammer, 1992;King, Ollendick, Mattis, Yang, & Tonge, 1996; Lau, Calamari, &Waraczynski, 1996; Macaulay & Kleinknecht, 1989). For instance, alarge community study of 2,365 high school students (mean age = 15.4years) found that 135 (5.7%) students reported a lifetime history of atleast one panic attack with four or more symptoms, and 62 (2.6%) re-ported at least one spontaneous panic attack (Hayward, Killen,Kraemer, & Taylor, 2000). Prevalence estimates of panic disorder inadolescence range from 0.5% (Hayward, Killen, & Taylor, 2003) to1.6% (Reed & Wittchen, 1998) in community samples.

In clinical samples, panic disorder is clearly a clinically relevantproblem, with estimates ranging from 6% (in a pediatric psycho-pharmacology clinic; Biederman et al., 1997) to approximately 10% (inboth an anxiety disorders clinic and an Italian outpatient clinic; Last &

2 CHILD & FAMILY BEHAVIOR THERAPY

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Strauss, 1989; Masi, Favilla, Mucci, & Millepiedi, 2000) of referredchildren and adolescents meet criteria for the disorder. Additionally,compared to psychiatric and non-clinical control groups, adolescentswho meet criteria for panic and/or agoraphobia have elevated comor-bidity with depression and other anxiety disorders (Biederman et al.,1997), and they report higher anxiety sensitivity compared to a clinicalcontrol sample of children without panic disorder (Kearney et al.,1997). This underscores the importance of developing efficacious treat-ments for children and adolescents who experience panic attacks andpanic disorder.

PANIC CONTROL TREATMENTFOR PANIC DISORDER AND AGORAPHOBIA

A number of studies have established the efficacy of cognitive-be-havioral treatments (CBT) for adults with panic disorder and agora-phobia (Clark, 1989; Clark, Salkavakis, Hackmann, Middleton, Anasta-siades, & Gelder, 1994; Telch, Schmidt, Jaimez, & Harrington, 1995).Panic Control Treatment (PCT) is one such cognitive-behavioral treat-ment developed by Barlow and Craske (2000) in the mid-1980s. PCThas been found to be superior to progressive muscle relaxation andwaitlist control groups at both post-treatment and follow-up (Barlow,Craske, Cerny, & Klosko, 1989; Craske, Brown, & Barlow, 1991), andit appears to have a more durable effect at follow-up than tricyclicmedication for panic-disordered patients (Barlow, Gorman, Shear, &Woods, 2000).

Ollendick (1995) conducted the first controlled study of CBT forpanic-disordered adolescents, which employed a multiple-baseline de-sign with four participants (ages 13 to 17). The treatment containedcomponents of PCT, but also included progressive muscle relaxationand situational exposure. At post-treatment, all adolescents reported areduction in the frequency of panic attacks, less situational avoidance,and lower scores on self-report questionnaires of anxiety sensitivity,fear, and overall anxiety (Ollendick, 1995).

Given the efficacy of PCT with panic-disordered adults, as well asOllendick’s finding that CBT can be successfully applied to adolescentswith panic disorder, Mattis and colleagues (Hoffman & Mattis, 2000;Mattis & Ollendick, 2002) developed a developmentally sensitive adap-tation of the PCT protocol for adolescents. Panic Control Treatment forAdolescents (PCT-A) shares its predecessor’s focus on three main as-

Micco et al. 3

pects of panic disorder. Specifically, PCT-A targets: (1) the cognitive,or misinterpretational, aspect, (2) the hyperventilatory response, and (3)conditioned reactions to physical sensations. However, several changesin the protocol were made so that it would be more appropriate for usewith adolescents. These changes include clearer, simplified language(particularly during the psychoeducational component of the manual)and visual and verbal examples of important concepts. Situational ex-posure was also added to the PCT-A manual, given the high frequencyof agoraphobic avoidance in panic-disordered adolescents (Biedermanet al., 1997; Kearney et al., 1997).

Results of a recent, randomized controlled trial of PCT-A support theefficacy of the treatment protocol with adolescents who have been diag-nosed with panic disorder and agoraphobia (Mattis, Cohen, Hoffman,Pincus, Choate, & Micco, 2001; Mattis & Pincus, 2003; Mattis, Pincus,Ehrenreich, & Barlow, 2006). Compared to adolescents randomly as-signed to a waitlist control group and assessed post-waitlist, adolescentsassigned to the treatment group showed significantly greater improve-ments on clinician severity ratings of panic disorder, the Multidimen-sional Anxiety Scale for Children (MASC; March, 1997), and theRevised Children’s Manifest Anxiety Scale (RCMAS; Reynolds &Richmond, 1978) at post-treatment assessment (Mattis et al., 2006),among other measures (see Mattis et al., 2006, for a full review of thestudy’s findings).

TREATMENT COMPONENTS OF PCT-A:DESCRIPTION AND RATIONALE

PCT-A consists of 11 individual treatment sessions that are 60-90 min-utes in length. There are seven main treatment components of PCT-A,which are described in Table 1. Breathing retraining is introduced in ses-sion three, following psychoeducation (session one) and situation expo-sure (session two). The inclusion of breathing retraining is based on thehyperventilation model of panic disorder, which holds that subtle,chronic hyperventilation (or overbreathing) in people with panic disorderleads to physical symptoms that, when noticed, can spiral into afull-blown panic attack (Ley, 1985). In support of this model, studieshave shown that people with panic disorder have lower basal pCO2 levels(Roth, Wilhelm, & Trabert, 1998; Papp et al., 1997) and greater subjec-tive response to voluntary hyperventilation (Rapee, Brown, Antony, &Barlow, 1992). Breathing retraining is intended to correct the patient’s

4 CHILD & FAMILY BEHAVIOR THERAPY

tendency towards subtle hyperventilation, and thus decrease physicalsensations that predispose the patient to experience a panic attack.

The rationale for including cognitive restructuring and hypothesistesting in PCT-A is based on Clark’s (1988) cognitive model of panic,which holds that catastrophic misinterpretation of normal physiologicalanxiety reactions result in panic attacks. Indeed, adult patients withpanic disorder are more likely than patients with other anxiety disordersand adults with no psychiatric disorder to interpret ambiguous physicalsensations as something being physically or mentally wrong with them(Clark et al., 1997). Cognitive restructuring addresses this misinter-

Micco et al. 5

TABLE 1. Treatment Components Included in PCT-A

Treatment Component Session(s)Introduced

Description

Psychoeducation 1-2 Therapist provides accurate information aboutfeared physical sensations in the context ofthe body’s fight/flight system and describesand discusses the “cycle of panic”

Situational Exposure (SE) 2 Fear and Avoidance Hierarchy is developed;therapist emphasizes that remaining in fearedsituations will lead to habituation inpanic-related symptoms; exposure from FAHis assigned at each session

Breathing Retraining (BR) 3-4 Adolescent is taught to breathe slowly fromthe diaphragm and practices twice daily athome

Cognitive Restructuring (CR) 4-5 Described as “thinking like a detective”;adolescent learns to identify automaticthoughts, including probability overestimationand catastrophic thinking, and is taught tochallenge thoughts by looking at the evidenceand generating rational responses

Interoceptive Exposure (IE) 5-6 Adolescent is desensitized to panic-likephysical sensations through a series ofexercises designed to elicit these sensations,such as spinning in a chair, breathing througha straw, and hyperventilating; exercises arerepeatedly practiced in several settings untilthe sensations do not elicit anxiety

Hypothesis Testing 7 Adolescent makes predictions regarding theoutcome of a feared situation, engages in thesituation, and evaluates his/her originalprediction

Naturalistic InteroceptiveExposure

8 Adolescent engages in situations in everydaylife that elicit physical sensations (i.e.,drinking caffeine, exercising, going on a rollercoaster)

pretational aspect of panic disorder, as does hypothesis testing (behav-ioral experiments that test the accuracy of panic-related cognitions).

Children and adolescents with panic disorder and panic attacks aremore likely to experience anxiety sensitivity, or hypervigilance and fearof physiological sensations than children and adolescents without panicdisorder or panic attacks (Calamari et al., 2001; Ginsburg & Drake,2002; Kearney et al., 1997; Weems, Hayward, Killen, & Taylor, 2002).Thus, helping adolescents with panic disorder become less fearful andvigilant of normal physiological sensations appears to be an importanttreatment goal, and this is the purpose of interoceptive exposure.

Although PCT-A is primarily an individual treatment, parents are in-cluded in the last 10 minutes of sessions one, four, seven, and 11 ofPCT-A. Given that parents are integrally involved in their adolescents’lives, it is expected that including them as part of therapy will result ingreater reinforcement of the use of cognitive-behavioral skills at home,although more research is necessary to determine if this is the case(Barrett, 2000).

IDENTIFYING EFFICACIOUSTREATMENT COMPONENTS OF PCT

Examination of Specific Treatment Components of PCT in Adults

Identifying components of a treatment that most effectively lead tosymptom reduction allows researchers to “fine tune” the treatment manualsthey develop and clinicians to spend more time on aspects of treatment thatseem to work. There are a number of studies that have examined the effi-cacy of specific cognitive-behavioral treatment components for adults withpanic disorder, many of which have compared interoceptive exposure (IE)to other treatment components (Arntz, 2002; Bouchard et al., 1996; Craske,Rowe, Lewin, & Noriega-Dimitri, 1997; Hecker, Fink, Vogeltanz, Thorpe,& Sigmon, 1998; Ito, Noshirvani, Basoglu, & Marks, 1996). For instance,Hecker and colleagues (1998) provided 18 patients with panic disorderwith four sessions of cognitive therapy (CT) and four sessions of IE; half ofthe patients got CT first, and half got IE first. Results show that both treat-ments led to similar clinical improvements, with the only difference beinglower self-ratings of global disturbance in the CT-first group. The order ofthe treatment components did not influence outcome, as most patientsmade clinically significant treatment gains during the first half of treatmentand maintained them during the second half (Hecker et al., 1998). Another

6 CHILD & FAMILY BEHAVIOR THERAPY

study randomly assigned 26 patients with panic disorder and agoraphobiato 10 weekly sessions of IE plus situational exposure (SE) or SE alone; nei-ther treatment condition included CT (Ito et al., 1996). There were few dif-ferences in treatment outcome between the two groups, although morepatients who had both IE and SE improved greater than 50% on measuresof apprehension and agoraphobia (Ito et al., 1996).

Craske et al. (1997) compared IE to breathing retraining (BR) in agroup of 38 adults with panic disorder and agoraphobia. All patientswere treated using cognitive restructuring and SE, but half also receivedIE while the other half received BR. While both treatment packageswere equally effective on a number of panic-relevant measures, thosewho had received IE (compared to those who received BR) had fewerpanic attacks and lower overall severity at post-treatment and fewerpanic attacks and phobic fears at six-month follow-up (Craske et al.,1997). Schmidt and colleagues (2000) found that adults with panic dis-order and agoraphobia who received BR in combination with SE tendedto have lower end-state functioning at a follow-up assessment whencompared to adults who received SE without BR. The authors suggestthat this finding may be due to patients using deep breathing in an at-tempt to avoid panicky physical sensations during panic attacks(Schmidt et al., 2000).

In sum, studies that have compared the efficacy of specific treatmentcomponents that are included in PCT for adults have found few differ-ences in overall outcome on panic-relevant measures, including panicattack frequency, apprehension of panic, and agoraphobic avoidance,although there is some evidence for the efficacy of IE and SE having anadvantage over that of BR in treatment outcome, particularly at fol-low-up. To date, however, no study has looked at specific treatmentcomponents of panic control treatment in children and adolescents.

“Sudden Gains” Treatment Studies

One way of examining the contribution of individual treatment com-ponents to overall improvement is to look at between-session treatmentchanges. If an abrupt reduction in symptoms occurs following a specificsession, a treatment component addressed in that session may have con-tributed to overall improvement. Tang and DeRubeis (1999) examinedbetween-session changes for adults receiving CBT for depression,particularly looking for abrupt changes from one session to the next, or“sudden gains” in treatment. The researchers found that significantcognitive changes (as measured by a clinician rating scale) tended to

Micco et al. 7

precede sudden gains on the Beck Depression Inventory (Tang &DeRubeis, 1999). Pham and colleagues (2004) found similar results intheir analysis of sudden gains on the Anxiety Sensitivity Index (ASI)for adults receiving CBT for panic disorder. Specifically, patients whomade sudden gains had significantly lower anxiety sensitivity atpost-treatment compared to patients who did not make sudden gains(Pham, Tang, Zinbarg, & Andrusyna, 2004). Thus, analysis of be-tween-session treatment change may contribute to an understanding ofthe contribution of treatment components and have an impact on treat-ment outcome.

AIMS OF THE PRESENT STUDY

Given that a sizeable number of adolescents and children present toclinical settings with panic disorder and agoraphobia or sub-syndromalpanic disorder, it is important to evaluate the efficacy of treatments pro-vided to this population. While PCT-A appears to be an efficacioustreatment for panic-disordered adolescents, it is unclear which compo-nents of the protocol actively contribute to the treatment’s efficacy.There have been a number of studies examining the relative efficacy ofspecific CBT components for adults with panic disorder but not for ado-lescents. The purpose of the present study is to conduct a preliminaryexamination of panic-related symptom changes in relation to the intro-duction of different treatment components of PCT-A, using suddengains analysis. However, in contrast to Tang and DeRubeis (1999), whocompared individuals who made sudden gains to those who did not, thepurpose of the present study is to identify when adolescents with panicdisorder as a group experienced significant improvements in panic-re-lated symptoms over the course of PCT-A. More specifically, wesought to generate hypotheses about the relative efficacy of the treat-ment components of PCT-A by determining which treatment compo-nents of PCT-A were followed by sudden treatment gains.

METHODS

Participants

The data used in the present analysis were drawn from a randomized,controlled trial of PCT-A at an outpatient anxiety disorders clinic. Thestudy included 21 adolescents (18 girls, three boys; mean age = 15.38,

8 CHILD & FAMILY BEHAVIOR THERAPY

SD = 1.16) who completed the treatment in its entirety. All adolescents,ages 13 to 17, who were principally diagnosed with panic disorder (withor without agoraphobia) at intake via the Anxiety Disorders InterviewSchedule, Child/Parent Version (ADIS-IV-C/P; Silverman & Albano,1996) between 1998 and 2002 were offered participation in the project.Exclusion criteria included diagnosis of a psychotic disorder, pervasivedevelopmental disorder, mental retardation, and current suicidal idea-tion. Adolescents taking psychiatric medication were required to takethe same dose of the medication for at least one month (for anti-anxietymedications) or three months (for anti-depressant medications) priorto participation in the project and remain on the same dose of medica-tion until the end of their participation in the study. Of those who wereoffered the project, 80% agreed to participate; the primary reason foradolescents choosing not to participate was not wanting to wait fortreatment should they be randomized to the waitlist condition of thestudy.

Adolescents who were eligible and agreed to participate in the proj-ect reviewed and signed informed consent and assent forms, along withtheir parents, after which they were randomly assigned to either thetreatment or waitlist condition. The latter involved bi-weekly, 30-min-utes “check-in” sessions over the course of eight weeks, during whichadolescents established rapport with their therapist and described anypanic-related symptoms they experienced over the course of the inter-vening two weeks. Other than the completion of weekly monitoringforms, waitlist sessions did not include any cognitive-behavioral treat-ment components. After the completion of the waitlist period, adoles-cents in this group received a full-course of PCT-A. Therapists includeddoctoral students in clinical psychology and doctoral-level psycholo-gists. All sessions were videotaped, and 32.5% of the sessions were ran-domly selected and reviewed for treatment integrity by either abachelor’s level research assistant or doctoral student. All session com-ponents were rated on a scale from 1 (not at all covered in session) to 5(completely and thoroughly covered in session) and then averaged tocreate one treatment adherence rating for the entire session. The averagetreatment adherence across sessions in this study was 4.57 (SD = .37).

Ten girls and two boys from the immediate treatment group com-pleted all the measures of interest to the present study. Two additionaladolescents, one girl and one boy, dropped out of treatment after sessioneight and are not included in the analyses below. Of the waitlist group,eight girls and one boy who chose to participate in treatment after com-pleting the waitlist period also completed all study measures; two girls

Micco et al. 9

and one boy chose not to participate in treatment after completing thewaitlist period. As the waitlist group did not differ from the immediatetreatment group prior to treatment initiation on measures of anxiety,panic disorder, depression, or anxiety sensitivity (Mattis et al., 2006),both groups were combined to analyze their treatment sessions. Thus,21 adolescents are included in the present study.

Despite efforts to recruit a more ethnically diverse sample, all partici-pants in the study were Caucasian. Most of the adolescents’ parentswere married (90%), while 10% were divorced or separated. The modallevel of education for both parents was a bachelor’s degree. Of the 21participants, 19 were diagnosed with panic disorder with agoraphobia atthe initial assessment, while two were diagnosed with panic disorderwithout agoraphobia. The mean clinician severity rating of panic disor-der, based on the ADIS-IV-C/P (zero to eight, with a CSR of four andhigher representing a clinical level of severity), was 5.52. Most of theparticipants (85.7%) had at least one additional clinical anxiety or mooddisorder; the mean number of additional diagnoses was 1.71.

Measures

Weekly Measures

Weekly Record of Anxiety and Depression (WRAD). The WRAD is amonitoring form on which adolescents recorded their daily levels of av-erage anxiety, depression, and pleasantness on a zero (not at all) to eight(very much) scale. In a study of younger children (grades 3-6), the useof a daily self-monitoring form to record anxiety symptoms was foundto be reliable, and the form differentiated test-anxious from non-test-anxious children (Beidel, Neal, & Lederer, 1991). Adolescents in thepresent study brought the WRAD to session each week and reviewed itwith their therapist. The present study used the “average anxiety” com-ponent of the WRAD. We averaged the adolescents’ daily anxiety rat-ings for each week, which yielded one average anxiety rating persession.

Panic Attack Record (PAR). Adolescents monitored the frequencyand qualitative aspects of panic attacks over the course of the week onthe PAR, a self-monitoring form initially developed for adults byRapee, Craske, and Barlow (1990). Adolescents were instructed to useone form per panic attack and to record the duration of the attack, maxi-mum anxiety level, possible antecedents, and symptoms. In a largelycollege-aged sample, Nelson and Clum (2002) found that the frequency

10 CHILD & FAMILY BEHAVIOR THERAPY

of panic attacks over a two-week period as measured by the PAR corre-lated highly (r = .89) with the frequency as measured by a Panic AttackFrequency Calendar. From the PAR, we calculated the average numberof unexpected, full-blown panic attacks (i.e., with four or more physicalor cognitive symptoms) adolescents experienced in the week prior toeach session of PCT-A.

Weekly Measure After Session 5

Belief Ratings. Belief ratings measured the degree to which adoles-cents engaged in “probability overestimation” and “catastrophic think-ing.” Probability overestimation is the tendency to think that events aremore likely to occur than evidence would suggest. Catastrophic think-ing is the tendency to believe that the consequences of a feared outcomewould be horrible and too difficult to handle. At session five, adoles-cents identified their most anxiety-provoking probability overestima-tion and rated the likelihood that the thought would come true (0 = not atall likely to 100 = very likely). In addition, adolescents identified theirworst catastrophic thought and rated their ability to cope if the fearedoutcome actually occurred (0 = very poorly to 100 = very well). At ev-ery session after session five, adolescents re-rated these two beliefs.

Measure Collected at Session 11

Perceptions of Treatment Questionnaire (PTQ). The PTQ is aself-report questionnaire, designed for the purposes of the PCT-Astudy, which includes both forced-choice and free-response questions.This measure assesses the aspects of treatment that adolescents did anddid not find to be helpful, such as specific treatment components andtherapist alliance. For the purposes of the present study, we only exam-ined adolescents’ responses to the free-response PTQ question, “Whatwas most helpful about the treatment?”

Data Analysis

Sudden gains, or treatment improvements, using group averages foreach measure were analyzed for each of the three weekly measures. Ifan adolescent did not complete a measure for a particular session, it wasnot replaced with an individual average and instead dropped from thecalculated group average for that particular session. Although suddengains have previously been examined across individuals completing

Micco et al. 11

treatment for depression (Tang & DeRubeis, 1999; Stiles et al., 2003),there is no precedent for examining sudden gains from session-to-ses-sion across group averages. Thus, for each measure, we defined the firstcriterion for a sudden gain as a between-session change score of at leasttwo standard deviations from the mean of all between-session changesacross the 11 sessions. This “two standard deviation” criterion ensuredthat sudden gains were large relative to overall changes. In addition,similar to criteria established in Tang and DeRubeis’ (1999) study, sud-den gains had to represent at least 25% of the pre-gain session’s WRADscore, panic attack frequency, or belief rating. Furthermore, to ensurethat the improvement was stable, the mean scores across the three ses-sions before the sudden gain had to be significantly higher than themean scores across the three sessions after the gain (when applicable),using a t-test with an alpha of 0.05. Finally, we examined the PTQ todetermine which treatment component adolescents perceived to bemost helpful during PCT-A.

RESULTS

Sudden Gains on WRAD, PAR, and Belief Ratings

The mean “average anxiety” score on the WRAD, as rated by the ad-olescents on a scale from zero to eight, was 2.90 (SD = 1.70) at pre-treatment and 1.20 (SD = 1.77) at session 11. The average between-ses-sion change across all sessions on the WRAD-Average Anxiety was adecrease of 0.15 units (SD = 0.33; range = �0.40-0.70). Thus, a be-tween-session change on the WRAD had to exceed 0.66 to meet the twoSD criterion as a sudden gain. The mean decrease in average anxiety be-tween sessions four and five was 0.70, which met the first criterion.This gain was also greater than 25% of the previous session’s mean av-erage anxiety rating of 0.30 (0.30 � 0.25 = 0.08). In addition, the meanaverage anxiety rating for the three sessions preceding the sudden gain(2.87) was significantly greater than that of the three sessions after thesudden gain (2.27; t = 10.39, p = 0.01). This significant improvement inaverage anxiety notably occurred after the introduction of cognitive re-structuring in the treatment protocol. No additional between-sessionchanges in average anxiety met sudden gain criteria (see Figure 1).

Adolescents experienced an average of 2.63 (SD = 3.50) panic at-tacks a week at pre-treatment, which decreased to 0.31 (SD = 0.58) atsession 11. The average between-session decrease in number of

12 CHILD & FAMILY BEHAVIOR THERAPY

full-blown panic attacks (as measured by the PAR) was 0.26 (SD =0.50; range = �0.25-1.50). In order to be considered a “sudden gain,” abetween-session change in frequency of panic attacks would have to ex-ceed 1.00. One between-session change met this criterion: the averagedecrease in panic attacks between sessions one and two (after the firstsession of psychoeducation) was 1.50 (see Figure 2). This between-ses-sion change met the second criterion to be considered a “sudden gain”;it was greater than at least 25% of the previous session’s panic attackfrequency of 2.88 (2.88 � 0.25 = 0.72). However, although the meannumber of panic attacks of the two sessions before the sudden gain(pre-treatment and session one; mean = 2.76) was greater than the meanfrequency of attacks in the three sessions after the sudden gain (1.53),this difference is not statistically significant. Thus, the decrease in panicattacks between sessions one and two cannot be considered a full sud-den gain. No other between-session changes on the PAR met the suddengain criteria.

Adolescents’ belief in their most salient probability overestimationdropped from a mean belief rating of 49.00 (SD = 35.12) at session fiveto 13.05 (SD = 25.73) at session 11. The mean between-session de-crease in adolescents’ belief ratings was 5.99 percentage points (SD =

Micco et al. 13

3.5

3

2.5

2

1.5

1

0.5

0Pre 1 2 3 4 5 6 7 8 9 10 11

Ave

rag

eA

nxi

ety

(0-8

)

Session

FIGURE 1. Mean change in average anxiety, as measured by the WRAD,across treatment sessions.

6.59; range = 0.55-18.83). One between-session change was greaterthan two standard deviations from the mean (13.18); between sessionsfive and six, the average decrease in adolescents’ belief ratings was18.83. Because belief ratings were recorded beginning at session five,the change between sessions five and six cannot be compared to beliefratings at earlier sessions. However, the belief rating at session five(49.00) is higher than the average belief rating of the three sessions fol-lowing the sudden gain (26.15). This sudden change in probabilityoverestimation belief came after the second session of cognitive re-structuring (see Figure 3). At the individual level, eight out of 21 partic-ipants (38.1%) experienced a rapid decrease in their belief ratingsbetween sessions five and six (i.e., a decrease that exceeded two stan-dard deviations from the individual’s mean change in belief ratingsfrom sessions five through 11).

Adolescent’s coping ratings (i.e., belief in how well they could copeif a feared outcome did occur) increased from an average of 56.57 (SD =30.70) at session five to 78.14 (SD = 29.56) at session 11. The mean be-tween-session increase in coping ratings was 3.60 percentage points(SD = 3.44; range = �1.20-9.48). The average increase in coping rat-ings between sessions five and six was 9.48, which is higher than two

14 CHILD & FAMILY BEHAVIOR THERAPY

3.5

3

2.5

2

1.5

1

0.5

0Pre 1 2 3 4 5 6 7 8 9 10 11

Ave

rag

e#

ofW

eekl

yP

anic

Att

acks

Session

FIGURE 2. Mean change in panic attack frequency, as measured by the PAR,across treatment sessions.

standard deviations from the mean (6.88). The mean coping rating atsession five (56.57) is lower than the average coping ratings at the twosessions following the sudden gain (69.59). Of the 21 participants,seven (33.3%) experienced an individual marked increase in their cop-ing ratings (i.e., greater than two standard deviations from their individ-ual mean change in coping ratings from sessions five to 11). No otherbetween-session changes in coping ratings met criteria to be considereda sudden gain (see Figure 3).

Adolescents’ Perceptions of Treatment

Adolescent participants were asked to give a free response to the fol-lowing question on the PTQ: “What was most helpful about the treat-ment?” Of the 19 participants who completed the PTQ, seven (36.8%)described cognitive restructuring as most helpful, while six (31.6%) feltthe psychoeducational component of treatment was most helpful. Three(15.8%) listed breathing retraining and two (10.5%) listed situationalexposure. One participant (5.3%) said that she found “having someoneto talk to” was most helpful to her.

Micco et al. 15

90

80

70

60

50

40

30

20

10

05 6 7 8 9 10 11

Session

Belief RatingCoping Rating

FIGURE 3. Mean change in probability overestimation belief ratings and cata-strophic cognition coping ratings across treatment sessions.

DISCUSSION

The present study is a preliminary examination of the relative effi-cacy of PCT-A treatment components with the aim of generating hy-potheses for additional controlled studies of this treatment. Our resultssuggest that over the course of PCT-A, adolescents experienced periodsof rapid improvement in panic-relevant symptoms. At pre-treatment,adolescents in this study experienced an average of 2.63 panic attacksper week, which is higher than the average weekly frequency of 0.92experienced by “severe” non-clinical adolescent panickers (calculatedfrom the three-week frequency of panic attacks), as reported byMacaulay and Kleinknecht (1989). After adolescents in the presentstudy received their first session of treatment, they experienced an aver-age of one-and-a-half fewer unexpected, full-blown panic attacks thanthey did the previous week. Although this decrease did not meet ourthird criterion to be termed a “sudden gain” (likely the result of onlyhaving only two sessions pre-gain on which to conduct the t-test), ado-lescents continued to experience fewer than two panic attacks per weekon average after session one, an improvement that is clinically mean-ingful. While this decrease in frequency of panic attacks may well bethe result of relief from initiating treatment, it is also possible that thedecrease is related to the first session of psychoeducation regardinganxiety and panic, which emphasizes the interrelationship betweenthoughts, physical sensations, and avoidance. Between sessions oneand two, each adolescent evaluated his/her own panic attacks in the con-text of the “cycle of panic” they learned at the first session. They werealso oriented to the treatment model by their therapist, which likelyresulted in an expectation of greater control over panic symptoms; thissense of control, in turn, may have led to a decrease in panic attacks.

Adolescents also experienced improvement in their ratings of aver-age anxiety between sessions four and five, as measured by the WRAD.This sudden gain occurred after the first session of cognitive restructur-ing (CR), during which adolescents learn how to gather evidenceagainst and challenge probability overestimations. Similarly, therewere significant cognitive improvements between sessions five and sixon two variables: how much adolescents believed their most salientprobability overestimation was true, and how confident they were intheir ability to deal with feared outcomes. These improvements oc-curred after the second session of CR, during which adolescents iden-tify catastrophic cognitions and determine ways that they could copewith feared outcomes if they actually occurred.

16 CHILD & FAMILY BEHAVIOR THERAPY

Thus, it appears that psychoeducation and CR are two treatmentcomponents after which sudden symptom improvements were ob-served, although further studies are essential to determining if these areindeed active treatment ingredients. Interestingly, these were the sametwo treatment components that adolescents reported as being most help-ful to them on the PTQ. However, given the limitations of our data, it isdifficult to determine if each treatment component led to improvementin the specific symptom of panic disorder it intended to target, mainlybecause of the overlap in the presentation of different treatment compo-nents. Nevertheless, our impression is that CR appeared to precede asignificant decrease in intensity of cognitive errors, as measured by thebelief and coping ratings, suggesting that there is specificity to thistreatment component. On the other hand, BR and IE did not result insudden decreases in panic attacks as would be expected, although thefrequency of panic attacks continued to decline steadily after bothtreatment components were fully introduced.

There are a number of limitations of this study that prevent us fromdrawing definitive conclusions about the relative importance of eachtreatment component. First, because of the overlap in the presentationof treatment components (for example, clients are still working on BRwhen they begin CR) and the lack of a control group, we cannot saywith certainty that the sudden gains we found were the direct result ofone particular treatment component. It was especially difficult to exam-ine what effect SE had on the adolescents’ symptoms of panic and ago-raphobia because this component was an active part of every sessionbeginning at session two and because the measure of avoidance in theoverarching study (the Fear and Avoidance Hierarchy) was not col-lected weekly over the course of the protocol. Also, while we can saythat there was a sustained decrease in cognitive errors on the belief rat-ing measure after session five, we cannot be certain that there were nochanges in adolescents’ belief ratings before the introduction of CR, asthis measure was not collected before session five (it was originallyconceived as a treatment tool).

A second limitation is the small sample size of 21 adolescents, all ofwhom were Caucasian. Most of the adolescents came from intact fami-lies and had well-educated parents. These characteristics of our samplemay limit the generalizability of the findings to other populations. In ad-dition, all participants in the present study were treatment completers;we may have found that some treatment components were less effectiveif participants who did not complete the full treatment had been in-cluded in the analyses. A third limitation is that there is no standard defi-

Micco et al. 17

nition of a “sudden gain” across group averages on a measure; thedefinition that we used was modeled after that of Tang and DeRubeis(1999), who looked at individual sudden gains, but our criterion thatsudden gains had to be larger than two standard deviations from themean on each measure was somewhat arbitrary, selected to ensure thatthe sudden gains we found were large compared to changes across treat-ment. However, this criterion may have missed between-sessionchanges that fell short of the two standard deviation criterion but werestill clinically significant. For future studies examining session-by-ses-sion changes, a standard definition of a mean “sudden gain” should beestablished so that the criteria are not reinvented with each study, whichlimits uniform interpretation of the results. Treatment outcome re-searchers seeking an established but conservative definition of suddentreatment gains may wish to employ the sudden gains criteria used inthe present study.

Finally, despite the fact that daily self-monitoring of anxiety andpanic attack records are widely used in cognitive-behavioral treatmentfor anxiety, there have been few studies of their psychometric proper-ties and none of the two measures designed particularly for the study ofPCT-A’s efficacy (the belief ratings and the PTQ). Nevertheless, it hasbeen shown that even children younger than the adolescents in thisstudy can reliably complete self-monitoring forms of anxiety symptoms(Beidel et al., 1991). Furthermore, the portion of the PTQ used in thepresent study for a qualitative analysis of what adolescents thought wasmost helpful during treatment was intended as a supplement to theirquantitative ratings. However, future studies of cognitive-behavioraltreatment components may wish to include well-validated self-reportmeasures that are collected on a weekly basis in addition to weeklyself-monitoring and in-session belief ratings.

While a number of controlled studies comparing CBT ingredientsfor panic disorder have been conducted with adults (i.e., Craske et al.,1997; Hecker et al., 1998), there have been no studies for CBT of ado-lescent panic, and very few studies in the child CBT literature in gen-eral, that have looked at the contribution of individual treatmentcomponents to a treatment manual as a whole. In a discussion of mech-anisms of change in cognitive-behavioral treatments for anxious chil-dren and adolescents, Hudson (2005) stresses the importance of futureresearch examining the differential efficacy of individual treatmentcomponents. Along these lines, we recommend that the “active ingre-dients” of PCT-A be examined more closely through controlled dis-mantling studies. For example, the efficacy of SE in PCT-A can be

18 CHILD & FAMILY BEHAVIOR THERAPY

established by comparing panic-disordered adolescents who receivestandard PCT-A to those who participate in PCT-A without the inclu-sion of SE.

The degree to which BR contributes to the overall efficacy of PCT-Ais of particular interest in light of Schmidt and colleagues (2000) find-ing that this treatment component may put adults with panic disorder atrisk for relapse, and Craske et al.’s (1997) finding that IE is superior toBR. Meuret, Wilhelm, Ritz, and Roth (2003) suggest that at this point,arguments for or against the inclusion of BR in treatment for panic dis-order are premature given the significant variability in studies that haveexamined this treatment component (i.e., type of BR used, patient selec-tion, study design). The authors argue that BR appears to correctmaladaptive breathing patterns that increase vulnerability to panic at-tacks and that further research is necessary to clarify the role of BR inthe treatment of panic disorder (Meuret et al., 2003).

In addition, given our finding that psychoeducation may have con-tributed to a significant reduction in average frequency of panic attacks,future research might examine if psychoeducation alone leads to theprevention of panic disorder and agoraphobia in adolescents at risk fordeveloping the disorder, such as adolescents who have parents withpanic disorder or adolescents who have previously experienced lim-ited-symptom panic attacks.

CONCLUSION

The fact that as many as 10% of children and adolescents presentingto outpatient clinics meet criteria for panic disorder emphasizes the im-portance of developing and honing efficacious treatments for this popu-lation. Evidence suggests that PCT-A results in significant treatmentimprovements in adolescents with panic disorder and agoraphobia(Mattis et al., 1996), although which components of this treatment con-tribute to its efficacy remain to be seen. Our session-by-session analysisof treatment gains on panic-relevant measures suggests that psycho-education may contribute to a reduction in the frequency of panic at-tacks, while cognitive restructuring appears to play a role in decreasingadolescents’ self-report of overall anxiety and the degree to which ado-lescents engage in cognitive errors. As clinical researchers develop in-creasingly helpful treatments for childhood anxiety disorders, it isparticularly important to obtain more definitive evidence of the treat-ment components (individually and/or in combination) that are neces-

Micco et al. 19

sary and sufficient to produce lasting treatment gains. Thus, werecommend that future research extend our findings by further elucidat-ing the role of each treatment component of PCT-A in reducing adoles-cents’ panic symptoms.

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RECEIVED: 8/18/06REVISED: 11/10/06

ACCEPTED: 11/20/06

doi:10.1300/J019v29n04_01

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