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Behaviour Research and Therapy 50 (2012) 797e804

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Behaviour Research and Therapy

journal homepage: www.elsevier .com/locate/brat

Shorter communication

Adjunctive mirror exposure for eating disorders: A randomized controlled pilotstudy

Tom Hildebrandt a,*, Katharine Loeb a,b, Sara Troupe a, Sherrie Delinsky c

a Eating and Weight Disorders Program, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 120, New York, NY 10029, USAb Fairleigh Dickinson University, 1000 River Road T-WH1-01, Teaneck, NJ 07666, USAcMcLean Hospital, Klarman Eating Disorder Center, 115 Mill St., Belmont, MA 02478, USA

a r t i c l e i n f o

Article history:Received 14 March 2012Received in revised form3 September 2012Accepted 15 September 2012

Keywords:Eating disordersMirror exposureBody image disturbanceLatent growth curve modelRandomized control trialAnxiety

* Corresponding author. Tel.: þ1 212 659 8673; faxE-mail addresses: tom.hildebrandt@mssm.e

(T. Hildebrandt), loeb@fdu.edu (K. Loeb), sara.trosdelinsky@mclean.harvard.edu (S. Delinsky).

0005-7967/$ e see front matter � 2012 Elsevier Ltd.http://dx.doi.org/10.1016/j.brat.2012.09.004

a b s t r a c t

Mirror exposure therapy has proven efficacious in improving body image among individuals with shape/weight concerns and eating disorders. No randomized controlled trials have examined the effect ofmirror exposure in a healthy-weight clinical sample of eating disordered individuals. The purpose of thecurrent study was to test the efficacy of a five-session acceptance based mirror exposure therapy(A-MET) versus a non directive body image therapy (ND) control as an adjunctive treatment to outpa-tient eating disorder treatment. Thirty-three males and females aged 14e65 with a body mass index of18.5e29.9 were randomized to five sessions of A-MET or ND with a 1-month follow-up. Results indicatedlarge to moderate effect size differences for efficacy of A-MET across measures of body checking, bodyimage dissatisfaction, and eating disorder symptoms (d ¼ �0.38 to �1.61) at end of treatment andfollow-up. Baseline measures of social comparison and history of appearance-related teasing werepredictive of treatment response. There were also differential effects of treatment on participants’perceived homework quality, but no differences in therapeutic alliance. Results suggest that A-MET isa promising adjunctive treatment for residual body image disturbance among normal and overweightindividuals undergoing treatment for an eating disorder. Future research and clinical implications arediscussed.

� 2012 Elsevier Ltd. All rights reserved.

Introduction

Mirror exposure therapy is a behavioral intervention designedto treat the core body image disturbances found among those witheating disorders or high shape and weight concerns. This inter-vention involves standing in front of a full-length mirror whileabstaining from ritualized checking or avoidance and habituating tothe associated negative emotions. Mirror exposure has been shownto reduce body dissatisfaction and improve affect and self-esteemin nonclinical (Delinsky & Wilson, 2006; Luethcke, McDaniel, &Becker, 2011) and underweight or overweight clinical samples(Hilbert, Tuschen-Caffier, & Vogele, 2002; Jansen et al., 2008; Keyet al., 2002). There have been no randomized controlled trials ofmirror exposure for individuals with an eating disorder in thehealthy or overweight BMI range.

: þ1 212 849 2561.du, hildebtb@hotmail.comupe@mssm.edu (S. Troupe),

All rights reserved.

Theoretically, mirror exposure works via breaking the associa-tion between negative affect and body exposure (Jansen et al.,2008; Key et al., 2002), but may also involve changes in cognitiveprocessing. Patients often either avoid or focus on specific bodyparts (i.e., local processing), causing them to lose sight of their bodyas one entity (i.e., global processing). Eye tracking studies havevalidated this selective visual attention and local processing bias(Jansen, Nederkoorn, & Mulkens, 2005), which may lead to diffi-culty characterizing a complex figure such as one’s body, and alsofacilitate negative evaluation. Specifically, attentional biases mayyield an overemphasis on imperfect body parts (Shafran, Lee,Cooper, Palmer, & Fairburn, 2007) which leads to a cycle ofheightened evaluation and avoidance. These cognitive aspects ofbody image pathology are targeted in mirror exposure through anacceptance-based intervention that requires both using nonjudg-mental language and a focus on integrating one’s appearance intothe more complex image of his or her body. Acceptance of one’sbody may be one way to neutralize the recurrent negativeevaluationeavoidance cycle.

The purpose of the present study is to test an adapted version ofDelinsky and Wilson’s (2006) mirror exposure therapy (MET)

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804798

compared to a non-directive control treatment for use in anoutpatient transdiagnostic sample of individuals with clinicallysignificant eating disorders. The treatment was expanded fromthree sessions to five to address the pathology encountered ina clinical sample and was employed adjunctively to existingspecialty eating disorder treatment. We hypothesized that thosereceiving the adapted MET would have greater changes in bodychecking and avoidance, body dissatisfaction, and obsessiveecompulsive eating disorder symptoms in comparison to the non-directive control. We based this hypothesis on the theory thatovervaluation of shape and weight is largely influenced byattentional and processing biases that maintain greater cognitiveeaffective coupling of visual perception and anxiety. Mirror exposureshould alter attentional biases by increasing global processing ofone’s body and simultaneously extinguishing the affective responseto one’s image. We also hypothesized that one’s personal disposi-tion toward societal pressures to be thin, the tendency to compareoneself to others on aspects of appearance, and history of beingteased, would be predictors of treatment response. We based thesepredictions on the well documented relationship between bothsocietal pressures and peer-based interactions for increased bodydissatisfaction and eating disorder symptoms (Presnell, Bearman, &Stice, 2004; Stice & Shaw, 2002).

Method

Participants

Forty-two individuals were recruited and screened fromspecialty treatment programs for eating disorders. As the CONSORTdiagram summarizes (see Fig. 1), thirty-three participants wereeligible, provided written consent, and were randomized to treat-ment. Inclusion criteria included (i) current DSM-IV eating disorder,(ii) between ages of 14e65, (iii) participating in concurrentpsychotherapy for an eating disorder. Eighteen of the 33 partici-pants received concurrent psychotherapy at the Mount Sinai Eatingand Weight Disorders Programdall of which were participating ineither Stage I of Cognitive Behavioral Treatment orMaudsley FamilyTherapy. Study therapists confirmed that the patients were

Fig. 1. CONSORT diagram describes stud flow and available data used in analyses. Two subjebehaviors. Both participants had active non-suicidal self-injurious behaviors upon entry in

receiving concurrent psychotherapy that did not include specificbody image interventions or focus. Exclusion criteria included (i)a bodymass index< 18.5 or 5th percentile ideal BMI for gender andage in adolescents and >29.9 BMI in adults or 85th percentile idealBMI for age in adolescents, and/or (ii) a change in dose or type ofpsychiatric medication in previous 4 weeks.

The study received approval from the Mount Sinai School ofMedicine’s institutional review board and all participants providedwritten informed consent. Participants were told that the studyaimed to compare the effects of two different treatments for bodyimage disturbance.

Assessments and primary outcomes

Upon signing consent, participants completed a baseline set ofinterviews and questionnaires. Body checking was monitoredweekly throughout treatment and all other primary outcomes weremeasured at baseline, end-of-treatment and one month follow-up.Interviewers were all research assistants that were trained by theauthors and required to reach >90% agreement with PI beforeconducting study interviews. All interviewers were blinded to thestudy treatment.

The Body Checking Questionnaire (BCQ; Reas, Whisenhunt,Netemeyer, & Williamson, 2002) assesses types and frequency ofbody checking behavior and Reas et al. reported the BCQ to havegood testeretest reliability and internal consistency (current studya ¼ 0.91), as well as concurrent validity with other assessments ofnegative body image.

The Yale-Brown-Cornell Eating Disorder Scale (YBC-EDS;Sunday, Halmi, & Einhorn, 1995) assesses eating disorder obses-sions/rituals and has established validity (Sunday et al., 1995).Internal consistency for the obsessions and rituals subscales werea ¼ 0.88 and a ¼ 0.91 for the study sample.

Participants completed the Body Shape Questionnaire (BSQ;Cooper, Taylor, Cooper, & Fairburn, 1987), which measures dissat-isfaction and preoccupations related to body shape within the pastfour weeks. Rosen, Jones, Ramirez, and Waxman (1996) reportedgood concurrent validity, internal consistency (a¼ 0.94 in the studysample), and testeretest reliability.

cts were withdrawn from the A-MET treatment because of acute increases in self-harmto the study.

Table 1Session by session description of mirror exposure and non directive therapy.

A-METa NDb

Session 1 1. Introduction and rationale2. Therapist models exposure exercise3. Patient completes exposure exercise4. Debriefing of exposure exercise5. Homework: Reduce one checking and avoidance behavior

through self-monitoring and choose outfit for next session

1. Introduction and rationale2. Discussion of personally relevant examples of

body image in patient’s life3. Discussion of impact of body image on daily life.4. Homework: Life chart of body image

Session 2 1. Review homework2. Complete steps 3e5 from session 1

1. Review homework2. Discussion of body image role in self-esteem.3. Homework: Keep diary of daily thoughts and feelings

about body imageSession 3 1. Same content as session 2, but exposures and homework increase

in difficulty by altering outfit or behavioral/avoidance target1. Review homework2. Discussion of how family and friends affect body image.3. Homework: Critical analysis of how friends and family affect

body imageSession 4 1. Same content as session 3, but exposures and homework increase

in difficulty.1. Review homework2. Discussion of media influence on body image.3. Homework: Critical analysis of media images using examples

from own life. Asked to bring these in for next session.Session 5 1. Same content as session 4, but exposures and homework increase

in difficulty.2. Summary of progress3. Plan for continuing changes in

acceptance and body checking/avoidance

1. Review homework2. Discussion of the larger sociocultural context and how cultural

upbringing affects body image3. Summary of progress4. Plan for continuing critical analysis of toxic environment.

a A-MET ¼ Acceptance Based Mirror Exposure Therapy.b ND ¼ Non Directive Body Image Therapy.

Table 2Differences between treatment groups on demographic variables.

Treatment p-value

A-METa (n ¼ 17) NDb (n ¼ 16)

Age 26.88 (10.68) 26.87 (4.52) 0.996BMIc 21.82 (1.88) 21.89 (2.69) 0.929% Female 88.2% 86.7% 0.893% Non-Hispanic 100% 100%% Caucasian 100.0% 93.3% 0.944% Asian 0% 6.7% 0.296Diagnosise 0.403% Anorexia nervosa in partial

remission11.8% 6.3%

% Bulimia nervosa 0% 12.6%% ED-NOSd 82.3% 75.0%% Binge eating disorder 5.9% 6.3%% Concurrent psychotherapy

outside of Mount Sinai46.7% 43.8% 0.755

% Currently take psychiatric meds 29.4% 25.0% 0.982

a A-MET ¼ Acceptance based Mirror Exposure Therapy.b ND ¼ Non Directive Therapy.c BMI ¼ Body mass index.d ED-NOS ¼ Eating disorder not otherwise specified.e Diagnosis made by EDE-Q and validated by clinical interview.

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804 799

Secondary outcomes and predictors

The Eating Disorder Examination-Questionnaire 4th edition(EDE-Q; Fairburn & Beglin, 1994) was used to assess the corefeatures of eating disorder pathology including four subscale scores(Restraint, Eating Concern, Weight Concern, and Shape Concern)with internal consistency ranging from a¼ 0.88 to 0.91 in the studysample.

The Body Parts Satisfaction and Dissatisfaction Scale (BPSDS;Berscheid, Walster, & Bohrnstedt, 1973), also referred to as the BodyPart Satisfaction Scale (BPSS; Noles, Cash, & Winstead, 1985; Mintz& Kashubeck, 1999) measures subjects’ satisfaction with theirbodies. The average score was used with averages above 3.0reflecting a general dissatisfaction with appearance and below 3.0reflecting a general satisfaction with appearance. The study sampleinternal consistency was a ¼ .86.

The Internalization Subscale of the Sociocultural AttitudesToward Appearance Questionnaire (SATAQ-Internalization;Heinberg, Thompson, & Stormer, 1995) measures thin-ideal inter-nalization. The SATAQ-Internalization subscale has establishedreliability (a ¼ 0.93 in current study) and validity (Cusumano &Thompson, 1997; Heinberg et al., 1995).

The Physical Appearance Comparison Scale (PACS; Thompson,Heinberg, & Tantleff, 1991) assesses the tendency to compareoneself to others on different aspects of appearance and had aninternal consistency in the study sample of a ¼ 0.84.

The Physical Appearance-Related Teasing Scale (PARTS;Thompson, Fabian, Moulton, Dunn, & Altabe, 1991) is a retrospec-tive self-report measure of the frequency of being teased whilegrowing up. Only theweigh/shape teasing (WST) subscale was usedin this study (a ¼ 0.88).

Treatment integrity and process measures

Alliance and homework quality were measured weekly after thefirst session.

The Helping Alliance Questionnaire (HAQ) is a measure of thequality of the therapeutic alliance (Alexander & Luborsky, 1984).Higher scores reflect greater satisfaction with the relationship

between the therapist and patient as well as therapy outcomes.Participants and therapists completed the HAQ at sessions twothrough five.

The Homework Rating Scale (HRS; Kazantzis, Deane, & Ronan,2004) is a 12-item measure of homework quality. Total sumscores for each version (Therapist and Patient) reflect overallhomework quality.

Randomization and treatments

Participants were randomly assigned to either treatment aftercompletion of consent procedures. Consecutively numberedenvelopes were sealed prior to beginning of the study withrandomization results and opened by the research staff memberwith the participant upon completion of the initial assessment.

Table 3Differences between treatment groups on baseline eating disorder symptoms.

A-METe (n ¼ 17) NDf (n ¼ 16) p-value

M (SD) M (SD)

EDE-Qa restraint 2.97 (1.55) 2.69 (1.42) 0.59EDE-Q eating 3.12 (2.34) 3.38 (1.94) 0.82EDE-Q shape 4.81 (0.95) 4.54 (0.1.54) 0.54EDE-Q weight 4.02 (1.22) 3.96 (1.37) 0.89EDE-Q OBEsg 2.25 (2.65) 4.14 (3.82) 0.28EDE-Q vomitingg h 0.13 (0.34) 1.89 (2.94) 0.08EDE-Q fastingg i 0.63 (1.15) 0.29 (0.47) 0.64BSQb 136.3 (24.86) 136.44 (22.65) 0.89BCQc 69.0 (11.96) 67.13 (13.72) 0.52YBOCEDd-preoccupation 21.33 (4.45) 19.67 (4.22) 0.28YBOCED-rituals 21.17 (6.56) 19.10 (7.42) 0.40

a EDE-Q ¼ Eating Disorder Examination Questionnaire.b BSQ ¼ Body Shape Questionnaire.c BCQ ¼ Body Checking Questionnaire total score.d YBOCED ¼ Yale-Brown Obsessive Compulsive Eating Disorder Scale.e A-MET ¼ Acceptance based Mirror Exposure Therapy.f ND ¼ Non Directive Therapy.g Independent Samples ManneWhitney U Test. OBE ¼ objective bulimic episode.h Making oneself sick/Vomiting (Item #16).i Extreme dietary restraint (Item #2).

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804800

Staff and patients were blind to randomization. After assignment,the participant was assigned a therapist to begin treatment.

Acceptance based mirror exposure

The A-MET treatment used in this study was an expandedversion of the three session manual used by Delinsky and Wilson(2006). Table 1 outlines the focus of each 50 min A-MET sessionwhich involved using a full-length single panel mirror for expo-sures. This process, repeated by the patient during all 5 sessions,involves the therapist monitoring the description for judgmentallanguage and redirecting the patient to use non-judgmentallanguage when deviations occurred. Therapists listened to ensurethat aspects of appearance were not avoided or scrutinized and tohelp the participant focus on integrating his or her description intothe whole image. Patients completed this task by describingthemselves from head to toe, using all available angles in front ofthe mirror and each exposure was intended to take approximately30 min. Therapists sat outside of view of the participant and ther-apists were careful not to engage participants in discussion ordistract them from the task. Therapists also collected subjectiveunits of distress (SUDS) ratings before exposure, approximately10 min into the exposure, immediately after the session, and beforethe end of session. After the exposure, the patient and therapistworked collaboratively on the homework assignment designed to

Table 4Model estimated changes in primary outcomes by treatment condition.

Baseline EOT

A-MET ND A-MET

BSQ 137.01 (35.44) 135.14 (33.96) 116.2 (BCQ 68.89 (3.42) 67.22 (3.67) 53.95 (Y-BOCS Obsession 22.03 (0.85) 20.08 (1.02) 18.75 (Y-BOCS Ritual 19.97 (1.45) 19.10 (1.62) 15.14 (

Note. Model estimated means and standard errors reported in each cell.EOT ¼ end of treatment.FU ¼ follow-up.BSQ ¼ Body Shape Questionnaire.BCQ ¼ Body Checking Questionnaire total score.Y-BCEDS ¼ Yale-Brown Obsessive Compulsive Eating Disorder Scale.A-MET ¼ acceptance based mirror exposure therapy.ND ¼ non directive body image therapy.

reduce body checking and avoidance and chose an outfit to wearduring the following exposure. The choice of outfit was designed tofollow a hierarchy of anxiety-provoking outfits. For example, thefirst exposure was often a “safe outfit” and by session five pro-gressing to a “going out” outfit or bathing suit.

Non directive therapy

The ND treatment was a five session adaptation of the Delinskyand Wilson (2006) control treatment. Table 1 outlines the fivesessions of ND therapy. Each session involved a topic relevant to thedevelopment and maintenance of body image disturbance. Thesetopics were only selected to be starting points or themes fordiscussion. Therapists’ maintained a supportive stance usingperson-centered therapy techniques such as reflective listening andaccurate empathy to validate the experience of the patient and helpthem clarify their own thoughts and feelings about the contentareas used to guide each session. Patients were given homeworkassignments consistent with the topic for each session with anemphasis on raising dissonance between the internalized ideal(thin or muscular) and personal experiences. Although the topicsand homework assignments were prescribed, the non directivestance of therapists prevented any prescriptions of behavioral orcognitive changes in session. Rather, any changes in these aspects ofbody image originated from the patient and were validated by thetherapist.

Therapist training

Eight different therapists having advanced graduate schoolstatus in a clinical psychology doctoral program or havingcompleted their doctorate received 8 h of training for the studytreatments by Drs. Hildebrandt and Delinsky. Separate 1-h groupsupervisions were provided for each treatment in which content ofeach session with each client was reviewed and discussed. Alltherapists provided both treatments to at least one study partici-pant during the course of study.

Statistical analyses

We conducted the primary analyses of treatment effects usinglatent growth curve modeling (Bollen & Curran, 2006). Thisstatistical approach allows for the modeling of both within-subjectchanges (i.e., BCQ, BSQ, or YBC-EDS) and between-subjects differ-ences (i.e., treatment effects) simultaneously. We conducted allanalyses using Mplus 6.12 (Muthén & Muthén, 2012). We modeledwithin-subject changes in BCQ using weekly session data and one-month follow-up or baseline, post-treatment, and one-month

1-Month FU

ND A-MET ND

32.88) 126.39 (34.54) 85.97 (44.89) 114.64 (40.84)3.60) 62.52 (3.51) 49.89 (3.84) 58.23 (4.02)1.03) 19.96 (0.98) 15.96 (1.29) 17.02 (1.44)1.33) 18.06 (1.41) 12.21 (2.21) 15.96 (2.24)

Table

5Su

mmaryof

conditional

latentgrow

thcu

rvemod

elsforprimaryou

tcom

es.

BCQa

BSQ

bYBC-EDS-Obc

YBC-EDS-Ri

Slop

eEO

TdFo

llow-U

pe

Slop

eEO

TFo

llow-up

Slop

eEO

TFo

llow-up

Slop

eEO

TFo

llow-up

Intercep

t62

.52(3.51)***

58.23(4.02)***

126.39

(34.54

)**

114.64

(40.84

)*19

.96(0.98)***17

.02(1.44)***

18.06(1.41)***15

.96(2.24)

Slop

e�1

.14(0.38)***

�4.88(2.40)*

�0.44(1.01)

�1.68(0.91)

Trea

tmen

t�3

.12(0.52)***�

14.94(5.74)**

�19.00

(5.58)***

�19.21

(3.69)***�9

.77(3.50)*

�28.67

(10.89

)�4

.58(1.37)***

�1.21(0.34)**

�1.08(0.51)*

�2.24(1.35)

�2.92(2.20)

�3.75(2.31)

Age

-0.001

(0.60)

0.21

(1.03)

0.34

4(1.32)

�0.03(1.54)

�1.00(1.74)

1.44

(2.30)

�0.01(0.89)

�1.23(1.67)

�1.02(1.55)

-0.03(1.05)

�1.12(1.78)

�1.43(2.03)

BMIf

0.25

(1.36)

0.05

(1.11)

1.01

(0.99)

1.11

(1.98)

2.26

(1.88)

1.89

(1.95)

1.32

(1.00)

1.78

(1.40)

1.20

(1.00)

0.02

(1.34)

0.00

4(2.01)

0.09

(1.88)

PARTS

g�0

.10(0.54)

7.88

(4.53)

7.49

(4.60)

�3.33(3.11)

9.45

(8.98)

7.75

(9.06)

�3.82(1.32)**

�0.44(1.47)

�4.26(1.80)*

0.51

(1.20)

�1.61(1.67)

�1.26(2.01)

SATA

Q-

Intern

alizationh

�1.77(1.02)

�1.82(1.34)

�2.03(1.46)

�1.32(1.30)

�3.45(1.88)

�6.70(2.22)*

�1.02(0.98)

1.74

(1.02)

1.99

(1.13)

0.58

(1.44)

0.32

(1.21)

0.55

(0.57)

PACSi

0.00

4(0.024

)0.38

(0.19)

0.37

(0.20)

0.33

(0.13)*

0.79

(0.38)*

1.08

(0.39)**

0.03

(0.06)

�0.001

(0.06)

0.03

(0.08)

�0.030

(0.05)

0.06

(0.07)

0.03

(0.09)

ReferralSo

urce

1.03

(1.00)

1.87

(1.49)

1.54

(1.78)

0.64

(1.30)

2.48

(1.79)

1.94

(1.88)

0.00

3(0.88)

�0.01(1.01)

-0.17(1.31)

-0.14(1.90)

�0.01(2.11)

-0.02(1.98)

Med

ication

0.00

3(1.03)

0.01

(1.00)

0.84

(1.30)

0.04

5(1.25)

0.02

(1.33)

0.32

(1.04)

0.01

(0.09)

0.42

(0.51)

0.57

(1.90)

0.85

(1.05)

0.94

(0.92)

1.11

(1.74)

Residual

Variance

0.59

(0.57)

143.27

(35.74

)***

139.72

(35.40

)***

68.10(54.10

)54

7.16

(143

.91)**

528.35

(139

.17)**

5.60

0(6.64)

8.11

(4.00)*

11.69(9.27)

2.29

(11.05

)20

.58(11.52

)16

.33(4.91)***

*¼

p<

.05.

**¼

p<

.01.

***¼

p<

.001

.aBCQ

¼Bod

yCheckingQuestion

naire

totalscore.

bBSQ

¼Bod

ySh

apeQuestion

naire.

cYBC-EDS¼

Yale-BrownObs

essive

Com

pulsiveEa

tingDisorder

ScaleOb¼

obsessionsor

Ri¼

ritualssu

bscale.

dEO

T¼

Endof

trea

tmen

tintercep

t.eFo

llow-up¼

intercep

tat

follo

w-up.

fBMI¼

bodymassindex

.gPA

RTS

¼Ph

ysical

Appea

rance-R

elated

TeasingScale.

hSA

TAQ-Intern

alization¼

Intern

alizationSu

bscale

oftheSo

cioc

ulturalAttitudes

TowardAppea

rance

Question

naire.

iPA

CS¼

Physical

Appea

rance

Com

parison

Scale.

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804 801

follow-up data for other measures. We estimated all models usinga maximum likelihood (ML) estimator. We modeled missing datausing the expectation-maximization algorithm. Patterns of missingdata were evaluated and met all missing at random assumptions.Model building involved comparing linear and nonlinear models toestablish the best fitting unconditional model. The best fittingmodel was determined by comparative fit index (CFI), root squareerror of approximation (RMSEA); a CFI > 0.95 was consideredevidence for a good fit to the data and RMSEA< 0.06 (Hu & Bentler,1999). Follow-up analyses were conducted adding other baselinepredictors to the conditional model. Effect sizes are reported usingthe formula d ¼ (bintercept/SDpopulation; See Table 2).

Results

There were no baseline differences in demographics, diagnoses,medication status or baseline severity between study groups (seeTables 2 and 3). Participants had a mean BMI of 21.85 (SD ¼ 2.26)with an average age of 26.88 (SD ¼ 8.40; range 17e57). They wereprimarily female (87.5%, n ¼ 28), non-Hispanic Caucasian (96.9%,n ¼ 31), and receiving DSM-IV diagnosis of eating disorder nototherwise specified (EDNOS; 78.9%, n ¼ 26). Nine percent ofwomen had achieved recent weight restoration as part of theirtreatment and were classified as AN-weight restored (AN-WR)because they continued to meet remaining DSM-IV criteria for AN.

A total of 43.8% of participants were taking a stable dose ofpsychiatric medication and 56.3% were recruited from the MSSMEWDP.

Primary outcomes

A linear unconditional BCQ model (aBIC ¼ 1304.08, CFI ¼ 0.877,RMSEA ¼ 0.255) was tested against a quadratic model and a modelthat allowed time to be freely estimated for the follow-up period(i.e., a nonlinear spline). The latter model provided the best fitoverall to the data (aBIC ¼ 1080.21, CFI ¼ 0.971, RMSEA ¼ 0.06) andthe time estimate reflected a deceleration in the linear decline post-follow up. Means and standard errors are reported in Table 4. Linearmodels provided the best fit to the data for the BSQ (aBIC ¼ 859.45,CFI ¼ 0.99, RMSEA <0.001), the YBC-EDS obsessions subscale(aBIC ¼ 616.90, CFI ¼ 0.99, RMSEA <0.001), and the YBC-EDS ritualsubscale (aBIC ¼ 945.25, CFI ¼ 0.96, RMSEA ¼ 0.05).

Table 5 reports the model results for conditional models withtreatment and other covariates and the intercept centered on theend of treatment. The effect of treatment on BCQ total score wasstatistically significant for slope and intercept indicating a 14.94point lower BCQ total score at the end of treatment among those inthe A-MET condition (d ¼ �1.21) and a 19.03 point lower score atone month follow-up (d ¼ �1.61). This effect was independent ofbaseline level of BCQ as the covariance of the slope and interceptwhen centered at baseline was nonsignificant (COV ¼ �0.03,SE ¼ 3.48, p ¼ 0.99). Similar smaller effects were found for BSQ andboth subscales of the YBC-EDS subscales. Those randomized to A-MET reported on average a 9.77 point lower BSQ total score(d ¼ �0.41), a 1.2 point lower score in YBC-EDS obsessions(d ¼ �0.43), and a 2.92 point lower score in rituals (d ¼ �0.38) atthe end of treatment. Larger differences were evident at one monthfollow-up for BSQ (d¼�0.83), YBC-EDS obsessions (d¼�0.73), andrituals (d ¼ �0.92). All of the estimated treatment effects onsymptom change over time were significant except for the treat-ment effect for rituals.

Other covariate effects were observed. Those with a greatertendency to compare their appearance to others had significantlyworse response to treatment; for every one point greater in PACSscore at baseline, the participants had a 0.79 point increase in BSQ

Table 6Summary of treatment effects on models for secondary outcomes.

Base model Treatment effect on secondary outcomes Residuals

Slope Intercept Slope EOTa Slope EOT

EDE-Qb restraint �0.362 (0.171)* 2.324 (0.372)*** �0.439 (0.207)* �0.159 (0.493) 0.242 (0.093)*** 1.882 (0.479)***EDE-Q eating concern �0.274 (0.148) 2.607 (0.368)*** �0.465 (0.192)* �0.476 (0.498) 0.247 (0.158) 2.033 (0.501)***EDE-Q shape concern �0.045 (0.143) 4.530 (0.303)*** �1.002 (0.202)*** �0.834 (0.425)* 0.254 (0.113)* 1.322 (0.335)***EDE-Q weight concern �0.051 (0.094) 4.038 (0.327)*** �0.753 (0.131)*** �0.934 (0.444)* 0.100 (0.031)*** 1.570 (0.393)***BPSDSc �0.413 (0.085)*** 3.428 (0.166)*** 0.147 (0.118) 0.055 (0.227) 0.010 (0.089) 0.312 (0.086)***

Note. The intercept reflects the model estimated mean of the dependent variable for Non-Directive treatment. The treatment effect at EOT reflects the difference in meansbetween Non-Directive treatment and Acceptance-Based Mirror Exposure Treatment.* ¼ p < .05. ** ¼ p < .01. *** ¼ p < .001.

a EOT ¼ End of treatment.b EDE-Q ¼ Eating Disorder Examination-Questionnaire.c BPSDS ¼ Body Parts Satisfaction Dissatisfaction Scale.

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804802

total score at the end of treatment. Those with greater thin-idealinternalization had significantly lower BSQ scores at one monthfollow-up. The PARTS score was predictive of greater reductions inYBC-EDS obsession scores, but not changes in BCQ, BSQ, or YBC-EDSritual reductions. Age, BMI, and referral source (MSSM vs. Commu-nity) were all nonsignificant predictors of treatment response.

Secondary outcomes

Table 6 summarizes the treatment effects for secondaryoutcomes. Consistent with the primary outcomes, those receivingA-MET had a greater decrease in eating disorder symptoms. Bothdietary restraint and eating concern symptoms decreased ata greater rate among those receiving A-MET although thesedifferences were not significant at the end of treatment. However,those in the A-MET condition had greater reductions in shape andweight concerns that reached significance by the end of treatment.Changes in BPSDS scale scores indicated no treatment effectalthough the model estimated score indicated a slightly satisfiedview of one’s body that continued to improve in both treatmentsduring follow-up.

Alliance and homework quality

Table 7 summarizes the effect of treatment on therapeutic alli-ance and quality, completion, and value of homework. All modelswere within acceptable ranges for CFI and RMSEA. Patients andtherapists had similarly high ratings of alliance after thefirst sessionin both treatment conditions. There was no significant effect oftreatment on slope or evidence that alliance changed significantlyover time in either treatment. Patient ratings of homeworkengagement increased over time in both treatments. Those in A-METalso rated their homeworkmore poorly than those in the ND atfirst session indicating less favorable experience early in treatment.However, those in A-MET experienced a greater increase in self-rated HRS scores than those in ND over the course of treatment.

Table 7Summary of treatment effects on quality and integrity outcomes.

Base model Treatment effect on a

Slope Intercept Slope

HAQb 1.218 (0.658) 16.449 (2.396)*** 0.383 (0.875)HAQTb 0.003 (1.256) 15.994 (2.272)*** 2.741 (2.861)HRSc 5.669 (1.878)*** 15.932 (1.607)*** 9.631 (2.555)***HRSTc 1.050 (0.649) 24.200 (1.356)*** �0.281 (0.865)

Note. All questionnaires were completed prior to sessions 2e5 of treatment. Model estim* ¼ p < .05. ** ¼ p < .01. *** ¼ p < .001.

a EOT ¼ End of treatment.b HAQ/T ¼ Helping Alliance Questionnaire patient and therapist versions.c HRS/T ¼ Homework Rating Scale patient and therapist versions.

This increase was associated with significant differences in home-work quality between groups at the end of treatment.

Discussion

The results of this pilot trial support the preliminary efficacy ofA-MET for an add-on treatment to specialty eating disorder treat-ment among individuals with an eating disorder. Significantimprovements were evident in both treatments among mostprimary and secondary outcomes with A-MET being superior at theend of treatment and one-month follow-up. The effects of A-METwere largest for body checking, although moderate to large effectsizes were found for EDE-Q Shape and Weight Concern, BSQ, andthe obsessions subscale of the YBC-EDS. Effects were not as robustfor EDE-Q restraint, eating concern, or YBC-EDS rituals. Thesefindings are consistent with those reported by others in under-graduates (Delinsky &Wilson, 2006), community women (Shafran,Farrell, Lee, & Fairburn, 2009), obese BED patients (Hilbert et al.,2002). However, this study is the first RCT to evaluate the efficacyof A-MET in a mixed-gender transdiagnostic sample of eatingdisorder patients with BMI ranging from healthy to overweight.

Degree of social comparison was the only negative predictor oftreatment response; those participants with higher levels of socialcomparison had significantly lower reductions in body shapeevaluation. Heightened social comparison has been previouslylinked to body dissatisfaction, particularly when the comparisontarget is thinner or more attractive (Leahey & Crowther, 2008;Leahey, Crowther, & Ciesla, 2011) and is related to attentional biasesconfirmed by eye-tracking studies in clinic patients (Blechert,Nickert, Caffier, & Tuschen-Caffier, 2009). Thus, a similar patternof local processing biases may operate in the evaluation of othersand could be incorporated into expanded versions of A-MET.

There were no consistent baseline predictors of treatmentresponse across primary outcomes, which may be a result ofinadequate statistical power. Only history of teasing and thin-idealinternalization had prognostic value. Teasing predicted changes in

lliance and homework Residuals

EOTa Slope Intercept

5.416 (3.241) 2.540 (2.408) 66.121 (21.599)***2.552 (1.696) 2.309 (6.534) 45.842 (14.342)***

�4.342 (2.189)* 16.958 (6.428)** 2.781 (4.861)6.412 (1.805)*** 1.340 (0.876) 3.374 (3.941)

ated means correspond to the session 2 assessment.

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804 803

eating preoccupation over treatment and thin-ideal internalizationpredicted shape concern changes over follow-up. Teasing has beenconsistently associated with body image dissatisfaction (Menzelet al., 2010) and thin-ideal internalization with eating disorderrisk (Stice, 2002; Stice, Ng, & Shaw, 2010), but no clear reason forthis specificity exists. It is likely that the significant variability inparticipant response captured by treatment effects limited thestatistical power for these variables as unique predictors.

There were no baseline differences in therapeutic alliance orsignificant changes in alliance over the course of treatment, whichsuggests that the superiority of A-MET observed in this study wasnot a result of the relationship between therapist and patient. Weare encouraged by this finding as it has been demonstrated in otherrandomized trials with eating disordered patients (Waller, Evans, &Stringer, 2012) and it suggests that a strong therapeutic alliance canbe maintained in A-MET. Interestingly, participants’ perceptionabout the quality of homework was lower among those in theA-MET condition, but increased significantly over the course oftreatment. This may reflect the initial difficulty of reducing check-ing and avoidance behaviors and an increasing sense of agency thatevolved with practice over the treatment.

Recent attempts to dismantle the mechanisms of ME innonclinical samples suggests that the nonjudgmental descriptivecomponent is unnecessary (Moreno-Dominguez, Rodriguez-Ruiz,Fernandez-Santaella, Jansen, & Tuschen-Caffier, 2012) and thatasking participants to describe negative body image areas ina positive manner leads to greater increases in body satisfaction(Luethcke et al., 2011). Contrary to these findings, those receivingA-MET experienced significantly greater increases in body satis-faction and reductions in body dissatisfaction than those in nondirective treatment. It is possible that this discrepancy is a result ofdifferences between populations (nonclinical vs. clinical). Alterna-tively, the nonjudgmental intervention in this version of A-MET,which explicitly directed patients to attend to the whole body (asopposed to just neutral descriptions of specific parts described byLuethcke et al.) may have been a more efficacious nonjudgmentalintervention.

There are a number of limitations to this study. First, theadjunctive treatment was uncontrolled and it is impossible tofirmly disentangle the effects of treatment from that of theconcurrent eating disorder treatment. However, there were nosignificant effects of treatment setting, suggesting the minimaleffect of concurrent treatment was consistent across treatmenttype and referral source. Second, the sample included ages from 14to 65 and included both males and females with a range of diag-noses. Although these different populations had no statisticallysignificant effect on outcomes, it is possible that with largersamples and enough statistical power that group differences wouldemerge. An important finding and potential limitation to A-MET isthat it may not be appropriate for those with current self-harmbehaviors. Two subjects were withdrawn from this study due toacute increases in nonsuicidal self-injury. The reasons for this effectare not entirely clear although the intensity of the emotionalexposure may persist among these individuals. Finally, our follow-up periodwas limited duration, so it would be premature to assumethat this intervention has long lasting effects. It was clear, however,that participants on average continued to improve in both condi-tions for the month post-treatment.

Future directions

The initial efficacy of A-MET is promising, but this treatmentneeds to be tested in a dismantling study that embeds mirrorexposure into an existing treatment such as CBT or IPT. Body imagedisturbances improve with CBT-E (Fairburn et al., 2009) in the

absence of an in-session mirror intervention and it remains unclearwhether the robust effects of A-MET are valuable enough to moti-vate clinicians to overcome the practical difficulties of deliveringA-MET in community therapy settings. Mirror exposure has severaldifferent protocols with different nuanced alterations to theexposure process which will be important to understand for bothapplication to different populations (e.g., adolescents vs. adults) aswell as to understand the mechanisms of change responsible forA-MET’s potency. Importantly, we think it will be necessary todetermine whether A-MET’s effects are a result of changes ininformation processing (e.g., improved global processing), orchanges in negative affect via extinction.

Acknowledgments

This study was funded by a research award provided by ICAP toDr. Hildebrandt and the Mount Sinai School of Medicine.

References

Alexander, L., & Luborsky, L. (1984). Research on helping alliance. In L. Greenberg, &W. Pinsof (Eds.), The psychotherapeutic process: A research handbook. New York:Guilford Press.

Berscheid, E., Walster, E., & Bohrnstedt, G. (1973). Psychology Today, 7, 119e131.Blechert, J., Nickert, T., Caffier, D., & Tuschen-Caffier, B. (2009). Social comparison

and its relation to body dissatisfaction in bulimia nervosa: evidence from eyemovements. Psychosomatic Medicine, 71(8), 907e912.

Bollen, K. A., & Curran, P. J. (2006). Latent curve models: a structural equationapproach. Psychometrika, 72(4), 643e646.

Cooper, P. J., Taylor, M. J., Cooper, Z., & Fairburn, C. G. (1987). The development andvalidation of the body shape questionnaire. International Journal of EatingDisorders, 6(4), 485e494.

Cusumano, D. L., & Thompson, J. (1997). Body image and body shape ideals inmagazines: exposure, awareness, and internalization. Sex Roles, 37(9e10),701e721.

Delinsky, S. S., & Wilson, G. T. (2006). Mirror exposure for the treatment of bodyimage disturbance. International Journal of Eating Disorders, 39(2), 108e116.

Fairburn, C. G., & Beglin, S. J. (1994). Assessment of eating disorders: interview orself-report questionnaire? International Journal of Eating Disorders, 16(4),363e370.

Fairburn, C. G., Cooper, Z., Doll, H. A., O’Connor, M. E., Bohn, K., Hawker, D. M., et al.(2009). Transdiagnostic congnitive-behavior therapy for patients with eatingdisorders: a two-site trial with 60 week follow-up. American Journal ofPsychiatry, 166(3), 311e319.

Heinberg, L. J., Thompson, J. K., & Stormer, S. (1995). Development and validation ofthe sociocultural attitudes towards appearance questionnaire. InternationalJournal of Eating Disorders, 17(1), 81e89.

Hilbert, A., Tuschen-Caffier, B., & Vogele, C. (2002). Effects of prolonged andrepeated body image exposure in binge-eating disorder. Journal of Psychoso-matic Research, 52(3), 137e144.

Hu, L. T., & Bentler, P. M. (1999). Cutoff criteria for fit indexes in covariance structureanalysis: conventional criteria versus new alternatives. Structural EquationModeling, 6(1), 1e55.

Jansen, A., Bollen, D., Tuschen-Caffier, B., Roefs, A., Tanghe, A., & Braet, C. (2008).Mirror exposure reduces body dissatisfaction and anxiety in obese adolescents:a pilot study. Appetite, 51(1), 214e217.

Jansen, A., Nederkoorn, C., & Mulkens, S. (2005). Selective visual attention for uglyand beautiful body parts in eating disorders. Behaviour Research and Therapy,43(2), 183e196.

Kazantzis, N., Deane, F. P., & Ronan, K. R. (2004). Assessing compliance withhomework assignments: review and recommendations for clinical practice.Journal of Clinical Psychology, 60(6), 627e641.

Key, A., George, C. L., Beattie, D., Stammers, K., Lacey, H., & Waller, G. (2002). Bodyimage treatment within an inpatient program for anorexia nervosa: the role ofmirror exposure in the desensitization process. International Journal of EatingDisorders, 31(2), 185e190.

Leahey, T. M., & Crowther, J. H. (2008). An ecological momentary assessment ofcomparison target as a moderator of the effects of appearance-focused socialcomparisons. Body Image, 5(3), 307e311.

Leahey, T. M., Crowther, J. H., & Ciesla, J. A. (2011). An ecological momentaryassessment of the effects of weight and shape social comparisons on womenwith eating pathology, high body dissatisfaction, and low body dissatisfaction.Behavior Therapy, 42(2), 197e210.

Luethcke, C. A., McDaniel, L., & Becker, C. B. (2011). A comparison of mindfulness,nonjudgmental, and cognitive dissonance-based approaches to mirror expo-sure. Body Image: An International Journal of Research, 8(3), 251e258.

Menzel, J. E., Schaefer, L. M., Burke, N. L., Mayhew, L. L., Brannick, M. T., &Thompson, J. K. (2010). Appearance-related teasing, body dissatisfaction, anddisordered eating: a meta-analysis. Body Image, 7(4), 261e270.

T. Hildebrandt et al. / Behaviour Research and Therapy 50 (2012) 797e804804

Mintz, L., & Kashubeck, S. (1999). Body image and disordered eating among AsianAmerican and Caucasian college students. Psychology of Women Quarterly, 23,781e796.

Moreno-Dominguez, S., Rodriguez-Ruiz, S., Fernandez-Santaella, M. C., Jansen, A., &Tuschen-Caffier, B. (2012). Pure versus guided mirror exposure to reducebody dissatisfaction: a preliminary study with university women. BodyImage: An International Journal of Research, http://dx.doi.org/10.1016/j.bodyim.2011.12.001.

Muthén, L. K., & Muthén, B. O. (2012). Mplus (Version 6.12). Los Angeles, CA.Noles, S., Cash, T., & Winstead, B. (1985). Body image, physical attractive-

ness, and depression. Journal of Consulting and Clinical Psychology, 53(1),88e94.

Presnell, K., Bearman, S. K., & Stice, E. (2004). Risk factors for body dissatisfaction inadolescent boys and girls: a prospective study. [Research support, non-U.S. gov’tresearch support, U.S. gov’t, P.H.S.]. International Journal of Eating Disorders,36(4), 389e401.

Reas, D. L., Whisenhunt, B. L., Netemeyer, R., & Williamson, D. A. (2002).Development of the body checking questionnaire: a self-report measure ofbody checking behaviors. International Journal of Eating Disorders, 31(3),324e333.

Rosen, J. C., Jones, A., Ramirez, E., & Waxman, S. (1996). Body shape questionnaire:studies of validity and reliability. International Journal of Eating Disorders, 20(3),315e319.

Shafran, R., Farrell, C., Lee, M., & Fairburn, C. (2009). Brief cognitive behaviouraltherapy for extreme shape concern: an evaluation. British Journal of ClinicalPsychology, 48, 79e92.

Shafran, R., Lee, M., Cooper, Z., Palmer, R. L., & Fairburn, C. G. (2007). Attentional biasin eating disorders. International Journal of Eating Disorders, 40, 369e380.

Stice, E. (2002). Risk and maintenance factors for eating pathology: a meta-analyticreview. Psychological Bulletin, 128(5), 825e848.

Stice, E., Ng, J., & Shaw, H. (2010). Risk factors and prodromal eating pathology.[Review]. The Journal of Child Psychology and Psychiatry, 51(4), 518e525.

Stice, E., & Shaw, H. E. (2002). Role of body dissatisfaction in the onset and main-tenance of eating pathology: a synthesis of research findings. Journal ofPsychosomatic Research, 53(5), 985e993.

Sunday, S. R., Halmi, K. A., & Einhorn, A. (1995). The Yale-Brown-Cornell eatingdisorder scale: a new scale to assess eating disorders symptomatology. Inter-national Journal of Eating Disorders, 18(3), 237e245.

Thompson, J. K., Fabian, L. J., Moulton, D. O., Dunn, M. E., & Altabe, M. N. (1991).Development and validation of the physical appearance related teasing scale.Journal of Personality Assessment, 56(3), 513e521.

Thompson, J. K., Heinberg, L. J., & Tantleff, S. (1991). The physical appearancecomparison scale (PACS). The Behavior Therapist, 14, 174.

Waller, G., Evans, J., & Stringer, H. (2012). The therapeutic alliance in the early partof cognitive-behavioral therapy for the eating disorders. International Journal ofEating Disorders, 45(1), 63e69.