Emotion-Focused Therapy for Binge-Eating Disorder: A Pilot Randomized Control Trial


 Background:Research into psychotherapy for binge-eating disorder (BED) has focused mainly on cognitive behavioral therapies, but efficacy, failure to abstain, and dropout rates continue to be problematic. The experience of negative emotions is among the most accurate predictors for the occurrence of binge eating episodes in BED, suggesting benefits to exploring other psychological treatments with a more specific focus on the role of emotion. The present study aimed to build upon the emerging evidence for emotion-focused therapy (EFT) as a treatment for BED by examining the outcomes of a pilot randomized waitlist-controlled trial of individual EFT for BED.Methods:Twenty-one participants were assessed on the primary outcome measures of objective binge episodes, the number of days on which objective binge episodes occurred, and binge eating symptoms and the secondary outcome measures of anxiety and depressive symptoms. The treatment consisted of 12 weekly one-hour sessions of EFT for maladaptive emotions over three months. A series of between groups repeated measures analyses of variance (ANOVA) was used to test the hypothesis that those receiving the treatment would demonstrate a greater degree of improvement in primary outcome measures compared to participants on the waitlist. A series of within-groups repeated-measures ANOVA was then used to test the hypothesis that participation in the EFT intervention would result in significant improvements in the primary and secondary outcome measures from pre to post-therapy, and then maintained at each follow-up period.Results:Participants receiving the EFT demonstrated a greater degree of improvement in primary outcome measures compared to participants on the waitlist. Participation in the EFT intervention resulted in significant improvements in all primary outcome measures and anxiety, but not depressive symptoms. The intervention also demonstrated a relatively low dropout rate when compared to other psychological therapy interventions for BED.Conclusions:These findings provide further preliminary evidence that individual EFT may be an efficacious treatment for BED and provide support for more extensive randomized control trials to test the efficacy and effectiveness of EFT for BED further.Trial registration: The study was retrospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12620000563965) on the 14 May 2020https://www.anzctr.org.au/ACTRN12620000563965.aspx

binge episodes, the number of days on which binge episodes occurred, binge eating symptoms, anxiety, and depression. The treatment consisted of 12 weekly one-hour sessions of EFT over three months with 21 participants. Those receiving the EFT demonstrated a greater degree of improvement in binge episodes, the number of days on which binge episodes occurred, and binge eating symptoms compared to participants who did not receive the treatment. The EFT intervention resulted in signi cant improvements in binge episodes, the number of days on which binge episodes occurred, binge eating symptoms and anxiety but not depression. In conclusion, these ndings provide further preliminary evidence that individual EFT may be an e cacious treatment for BED. Further controlled studies are needed.
Binge-eating disorder (BED) is the most prevalent of all the eating disorders (1). There is an estimated prevalence rate of 2.5% to 4.5% in females and 1.0% to 3.0% in males based on international data (2) and a 3-month prevalence rate of 5.58% based on Australian data (3). The core symptoms include recurrent episodes of binge eating while experiencing a sense of lack of control in the absence of compensatory strategies (4). Not surprisingly, many individuals with BED also have comorbid emotional disorders (5) including anxiety (6,7)and depression (8,9).
Spielmans et al. (10) noted that for BED, both The National Institute of Clinical Excellence (NICE) in the United Kingdom and the American Psychiatric Association guidelines suggest that cognitive behavior therapy (CBT) is the psychological treatment of choice, with interpersonal therapy (IPT) and dialectical behavior therapy (DBT) serving as second-line interventions (11,12 ). A subsequent meta-analysis examined direct comparisons between psychological treatments for bulimia nervosa (BN) and BED and the role of moderating variables (e.g., the degree to which psychotherapy was bona de or not bona de) based upon criteria published in Wampold,et al. (13). The meta-analysis included 77 comparisons reported in 53 studies and results indicated that: bona de therapies outperformed non-bona de treatments; bona de CBT outperformed bona de non-CBT interventions by a statistically signi cant margin (only approaching statistical signi cance for BN and BED when examined individually), full CBT treatments offered no bene t over their components, and the distribution of effect size differences between bona de CBT treatments was homogeneously distributed around zero. There was little evidence supporting treatment speci city in psychotherapy for BN and BED.
A more recent meta-analysis estimated the prevalence of patients with BED who achieved binge-eating abstinence following psychological or behavioral treatments (14). The most common treatment delivered was CBT (either in a clinician-led or guided self-help format), and other interventions includebehavioral weight loss, behavioral weight loss combined with CBT, IPT, DBT,behavior therapy, non-speci c supportive therapy, mindfulness, psychodynamic therapy, and a combined psychotherapy approach. The total weighted percentage of treatment-completers who achieved abstinence at posttreatment was 50.9% and 50.30% at follow-up. The highest abstinence rate was observed in IPT, and clinician-led group treatments produced signi cantly higher posttreatment (but not follow-up) abstinence estimates than guided selfhelp treatments. The meta-analysis demonstrated that 50% of patients with BED do not fully respond to treatment, and there is, therefore, a need to explore other psychotherapies to improve these outcomes.
Individuals with BED often experience di culties with de cits in emotion regulation (15) which can be de ned as the "… attempt to in uence which emotions we have, when we have them, and how these emotions are experienced or expressed" (16, p. 224). The emotion regulation model of binge eating postulates that binge eating occurs in response to intolerable emotional experiences in the absence of more adaptive coping mechanisms (17).Binge eating represents an effort by an individual to regulate emotion by numbing, avoiding or soothing negative or overwhelming affect (18).It occurs in the absence of effective regulation skills related to experiencing and differentiating as well as attenuating and modulating emotions (19), and individuals with BED experience more intense emotions and more signi cant di culties in emotion regulation than individuals without BED (20).
Given that the experience of negative emotions is amongst the best predictors for the occurrence of binge eating episodes in BED (21), outcomes could be improved by psychological treatments with a more speci c focus on the role of emotion. Emotion-focused therapy (EFT) is a compelling treatment for eating disorders and offers a unique framework for understanding the pathogenesis of emotional di culties (either under-regulating or over-regulating affect) in this population (22). The goal of EFT is to assist clients in processing unpleasant emotions by attending to and increasing awareness and expression of emotion; learning to tolerate and regulate experience; re ecting upon and make meaning of emotion by symbolizing emotional experience in words; and transforming maladaptive emotions by activating healthy, adaptive emotions together with their associated needs and action tendencies (23). EFT allows the therapy to move beyond the tautological trap (24) of being "not ready to change" and to move forward in recovery work.
According to the EFT model, emotion organizes experience through emotion schemes, which are constructed from lived emotional experience (25). Central mechanisms of change in EFT include the use of adaptive emotion to transform maladaptive emotion schemes that are understood to generate chronic enduring pain and maintain rigid and maladaptive modes of responding to experience (26), and a successful therapeutic relationship, in which the client feels empathically heard, understood, supported and safe (27). This, in turn, alters dysfunctional behavior patterns and decreases the likelihood of eating disorder behaviors being used as an emotional coping mechanism (28). While there is a growing body of literature exploring the use of EFT for eating disorders (e.g., 22,23,29,30,), this literature has generally included mixed samples of BED, Anorexia Nervosa (AN) and BN with limited research focusing speci cally on BED To date, only two studies have examined the e cacy of EFT speci cally for BED. Compare and Tasca (31) comparedthe outcome of 20 weeks of emotionally focused group therapy (EFGT), aimed at helping clients change how they experienced and used their emotions, with combined therapy (CT) of EFGT plus dietary counselling, which sought to lower energy-dense food intake in 118 obese adults with BED. Binge episodes and weight signi cantly declined during both treatments; however, compared to EFGT CT resulted in more rapid weight loss across the weeks of therapy. The dropout rate for EFGT was only 6%.To date, our previous study has been the only study to examine the e cacy of individual EFT for BED (citation blinded for review). This study involved the use of a multiple baseline case series design in which individual EFT over 12 weeks, was applied to six female adult participants with BED, with followups at 2, 4-and 8-weeks posttreatment. All cases experienced reliable recovery from binge-eating psychopathology and also a signi cant decrease in binge-eating frequency. There was reliable improvement or recovery for eating and shape concerns for all cases, and improvement on weight concern for the majority of cases; and all cases experienced reliable recovery or improvement in overall emotion regulation. Most cases that were in the clinical range for anxiety at pre-treatmentrecovered,and all cases experienced reliable improvement in, or recovery from, depression. Three of the six cases experienced reliable recovery or improvement in alexithymia. There were no treatment dropouts.
Given the preliminary evidence of the usefulness of individual EFT for BED from our previous case series study, a more extensive pilot trial to further test the e cacy and dropout rate of individual EFT for BED is required. The current study presents results from a pilot randomized waitlist-controlled trial of individual EFT for BED. This pilot study provides not only a further test of the e cacy of BED for EFT, but also a test of the acceptability of the intervention and estimation of sample sizes needed for future larger randomized control trials examining EFT for BED (32).It was hypothesized that participation in the EFT intervention would result in signi cant improvements in objective binge episodes and days, and binge eating psychopathology(primary outcomes), and anxiety and depression psychopathology (secondary outcomes) compared with the wait-list control group.It was also hypothesized that EFT would result in a lower dropout rate compared to other psychological interventions for BED.

Design
This study is a pilot randomized control trial (RCT) designed to support the development of a future de nitive RCT and it builds upon ndings from an initial multiple baseline case series design of EFT for BED (citation blinded for review). Participants were initially randomly allocated to either an EFT treatment intervention or waitlist (12-week clinical monitoring preceding treatment)using a block randomization method (33). This is a commonly used technique in clinical trial design which reduced bias and achieves sample size balance when allocating participants to treatment groups. It is particularly useful for smaller sample sizes and increases the probability that each allocation arm will contain an equal number of Participants Participants were recruited from local General Practitioners/Primary Care Physicians. Inclusion criteria included the following: being between 18 and 65 years of age, meeting the Diagnostic and Statistical Manual of Mental Disorders: DSM-V American Psychiatric Association -DSM-5 (2013) diagnostic criteria for BED, and possessing su cient English language skills to provide informed consent and participate in the study without translation. The exclusion criteria included current psychosis, intellectual disability, high suicide risk, drug or alcohol abuse, concurrent treatment for obesity, pregnancy, and the presence of AN or BN.The sample consisted of 21 participants, of whom 17 were female, and 4 were male. The average age was 44.52 (SD=11.89) years and the average age at rst binge 18.23 (SD=8.07) years. Ten participants were married or living with someone as married, 5 separated, 3 never married, 2 divorced and 1 widowed. Six participants had graduatedfour-yearcollege, 5 graduated two-year college or trade school, 4 completed grades 7-12 (without graduating high school), 3 graduated high school or high school equivalent, 2 partially completed college/trade school and 1 postgraduate/professional school. Eleven participants were employed full-time, 5part-time employment, 2 keeping house or caregiving full time,2 in school/training and 1 disabled.

Objective binge episodes and days
Changes in objective binge episodes and days (occurrence over the previous 7 days) were assessed using items from the Eating Disorder Examination Questionnaire -EDE-Q-6.0 (38). The EDE-Q-6.0 is a selfreport measure of eating disorder psychopathology based on the Eating Disorder Examination Interview (39). It is a widely used measure of eating disorder attitudes and behaviors in both community and clinical populations (40). The EDE-Q-6.0 also provides frequency data on the number of episodes of the eating disorder behavior and the number of days on which the behavior occurred. The items used to measure objective binge episodes (i.e.,a discrete episode of overeating of an objectively large amount of food associated with a feeling of loss of control) in the current study were: "Over the past 7 days how many times have you eaten what other people would regard as an unusually large amount of food (given the circumstances)?" and "On how many of these times did you have a sense of having lost control over your eating (at the time that you were eating)?". The item used to measure the number of days objective binge episodes occurred was "Over the past 7 days, on how many days have such episodes of overeating occurred (i.e., you have eaten an unusually large amount of food and have had a sense of loss of control at the time)?". The EDE-Q-6.0 has received support as a reliable and valid measure of eating-related pathology and speci c disordered eating behaviors (41,42). Test-retest reliability across studies ranges from 0.66 to 0.94 for scores on the four subscales (43). The EDEQ-Q-6.0 has demonstrated acceptable levels of internal consistency (α = .90) for the total score in a clinical sample (44). There are no standardized clinical cut-offs (38).

Binge eating psychopathology
Changes in binge-eating psychopathology were assessed using the Binge Eating Scale -BES (45). The BES is a commonly used self-report screening tool for binge eating in clinical practice and research.

Psychiatric comorbidity
Anxiety and depression were assessed using the Beck Anxiety Inventory -BAI (50) and Beck Depression Inventory-II -BDI-II (51). The BAI is one of the most used clinical self-rating scales for measuring the intensity of anxiety (52). Respondents are presented with a list of 21 common symptoms of anxiety and indicate how much they have been bothered by that symptom during the past month. Items are rated on a scale of 0 = not at all to 3 = severely. The total score is calculated by summing the ratings for the 21 items with amaximum possible score of 63. The BAI has high internal consistency (.93) and good testretest reliability (.75) (53), in addition to robust convergent and discriminant validity (54). Standardized cut off scores are as follows: 0-21 = low anxiety, 22-35 = moderate anxiety and >36 = potentially concerning levels of anxiety.
The BDI-II is one of the most widely adopted measures of depressive symptoms (55). The BDI-II measures both cognitive-affective (negative mood or negative affect) and somatic (fatigue or loss of energy) dimensions of depressive symptoms (56). Respondents read 21 groups of statements and then choose the one statement in each group that best describes the way he/she felt in the previous two weeks. Items are rated on a scale of 0 to 3, with higher ratings indicating more severe depressive symptoms. The total score is calculated by summing the 21 items, and the maximum possible score is 63. The BDI-II has sound psychometric properties with high internal consistency (α=.89) within the BED population. (9). It also has high test-retest reliability (r=.73 to .96)and sound concurrent, content, and structural validity across other populations (57). Standardized cut-offs are as follows: 0-13 = minimal depression, 14-19 = mild depression, 20-28 = moderate depression and 29-63 = severe depression (53).

Therapy retention
Participants who completely discontinued attendance were considered dropouts.

Procedures
Participants were initially telephone-screened for BED based on diagnostic criteria, according to DSM-5 (2013). Twenty-eight participants were telephone-screened, of which ve did not meet the diagnostic criteria for BED. Twenty-three participants meeting the diagnostic criteria for BED then completed the SCID-5-RV administered by a research assistant with training in clinical psychology. All met the inclusion criteria, but 1 participant chose not to participate due to being unable to commit fully to weekly treatment sessions, and 1 participant did not respond to contact attempts. Twenty-oneparticipants were randomly allocated to either an EFT intervention or 12-week waitlist using a block randomization methodby a statistician independent to the research team.
Participants allocated to the EFT intervention initially completed the BES, EDE-Q-6.0, BDI-II and BAI at pretherapy (Week 0). The BES and EDE-Q-6.0 were completed weekly during treatment (Weeks 1-12), and the BES, EDE-Q-6.0, BDI-II and BAI were completed at follow-up (Weeks 16, 20 and 24). Participants allocated to the waitlist control completed the BES, EDE-Q-6.0, BDI-II and BAI at pretherapy (Week 0), and then again 12 weeks later post waitlist period completion. Waitlist control participant then commenced 12 weekly treatment sessions and followed the same protocol as participants initially allocated to the treatment intervention. The therapist was blind to all assessments and randomizations of the participants.

Treatment
Treatment incorporated 12 weekly one-hour sessions of EFT for maladaptive emotionsover three months.
The treatment manual was initially adapted from Wnuk et al. (30) by (citation blinded for review)in a series of case studies exploring the use of individual EFT to treat BED. Phase 1 of the treatment focused on promoting awareness of emotions, welcoming and accepting emotions, putting emotions into words, and identifying primary emotions. Phase 2 focused on evaluating whether the primary emotion was adaptive or maladaptive, identifying destructive emotions, accessing other adaptive emotions and needs, and transforming maladaptive emotion schemes. Six main marker guided interventions were used in treatment in line with EFT protocol (25,27). These were:1. Empathic attunement and validation for vulnerability and establishing thetherapeutic alliance 2. Evocative unfolding for problematic reactions 3. Experiential focusing for unclear feelings 4. Two-chair dialoguesfor self-critical splits 5. Two-chair enactmentfor self-interruptive splits and 6. Empty chair work for un nished business.

Therapist
The therapist was the rst author, a Clinical Psychologist with 25 years of practice experience who had undergone Level 1, 2 and 3 training in EFT at the York University Psychology Clinic with the primary developer of this approach, Distinguished Professor Emeritus, Leslie Greenberg. The therapist had approximately four years of EFT-speci c practice experience before the study and was not involved in the initial treatment/waitlist randomization process, data collection before or during the study, or data analysis until after the study. Supervision was provided by Distinguished Professor Emeritus, Leslie Greenberg who was also a co-author of the original treatment manual used as a basis for therapy within the current study. Adherence to EFT protocol was reviewedand recti ed where necessary -during supervision based on video recordings of study treatment sessions.

Statistical Analyses Plan
Initially, abetween-groupexamination was conducted in relation to any signi cant differences between the 10 participants in the EFT intervention and 10 participants in the waitlist control on demographics at baseline. A series of 2 (Group) x 2 (Time) repeated measures analyses of variance (ANOVA) were then used to test the hypothesis that those receiving the treatment would demonstrate a greater degree of improvement on primary outcomes measures relating to objective binge episodes and days, and binge eating psychopathology compared to participants on the waitlist.. Following the between-group analysis, a within-group examination was then conducted in relation to any signi cant differences between the 20 participants who completed treatment on demographics. A series of within-groups repeated measures analyses of variance (ANOVA) was then conducted to test the hypothesis that participation in the EFT intervention would result in signi cant improvements in the primary and secondary outcome measures from pre to post-therapy and then maintained at each follow-up period

Demographics
Between-group differences No signi cant differences were found between the intervention and waitlist control groups in relation to mean age (years), mean age at rst binge (years), gender, marital status, education, and employment status. See Table 1.    Within-group changes Figure 2 and Table 3 outline within-group changes. Objective binge episodes.
There was a signi cant decrease in objective binge episode frequency within-group scoresmeasured over  Table 3.
Objective binge episode days.
There was a signi cant decrease in objective binge episode days within-group scores measured over  Table 3]. Pre to posttherapy, the number of participants with severe binge eating range decreased from 14 to 6, and the number of non-binge eating participants increased from 3 to 11. There were 3 participants with mild to moderate binge eating at pre and posttherapy.  Table 3]. At pretherapy, there were 3 participants in the severe range, 3 moderate, 5 mild, and 9 minimal.
Depression psychopathology.  Table 3). At pretherapy, there were 2 participants in the severe range, 5 moderate, 5 mild and 8 minimal. At 3monthfollow-up, there were 3 in the severe range, 4 moderate, and 13 minimal.
Therapy retention.
One participant (4.76%) dropped out after Week 4 of the EFT treatment for family health reasons. All completing participants attended all sessions.

Discussion
To our knowledge this is the rst pilot randomized controlled trial to test the e cacy of individual EFT for BED. Compared to participants on the waitlist, those receiving the EFT treatment demonstrated a signi cantly greater degree of improvement in objective binge episodes and days with large treatment effect sizes, and binge eating psychopathology with a moderate treatment effect size.An examination of the whole sample of treatment completers(20 participants) indicated that participation in the EFT intervention resulted in signi cant improvements in objective binge episodes and days, and binge eating psychopathology from pre to post-therapy and that these gains were maintained over follow-up.
Treatment gains in relation to objective binge episodes and days, and binge eating psychopathologywere maintained at 3 monthsfollow-up. Interestingly, however, there was a consistent decrease in mean binge eating psychopathology scores from post-therapy (Week 12) through to 3 monthsfollow-up (24 weeks), whereas objective binge episode frequency and objective binge episode days scores uctuated.These changes, however, from posttherapy and 3 monthsfollow-up were not statistically signi cant.
The number of participants classi ed as non-binge eating according to the BES in the current study was 11/20 (55%) at the end of treatment and 12/20 (60%) at three months follow up; and weekly mean objective binge episodes (in the previous 7 days) scores were 2.05 at the end of treatment and 1.45 at three months follow up. These ndings compare favorably with results from a systematic review and network meta-analysis of the comparative effectiveness of treatments for BED (59) where abstinence rates for therapist-led, partially therapist-led and structured self-help variants of CBT ranged from 17.9% to 86.7% at the end of treatment, and 20.8% to 84.6% at twelve-month follow-up; and binge episodes (in the previous 28 days) ranged from an average of 11.9 to .04 at the end of treatment, and 16.2 and .5 at twelve-month follow up (60,61,62).
The EFT for BED 4.76% dropout rate in the current study also compares favorably with dropout rates for other psychological treatment approaches for this condition including CBT -11.1% (63) and 21.3% (64); Guided self-help cognitive behavior therapy (CBTgsh) -30% (60); IPT -8.6% (59) and 7% dropout rate (65) In terms of changes to the secondary outcome measures, individual EFT for BED resulted in signi cant improvements in anxiety but not depression psychopathology. These ndings, however, need to be interpreted with caution given that 14 participants were in the mild or minimal range for anxiety psychopathology and 13 participants were in the mild or minimal range for depression psychopathology at pretherapy. This indicates that most participants were not experiencing severe or moderate anxiety or depression symptoms before completion of the EFT intervention. It is also noted that anxiety and depression psychopathology were only measured at pretherapy and follow-up but not during weekly treatment sessions which resulted in a brief snapshot of participant progress rather than a more accurate picture of changes over time.
The following future sample size calculations were made using GPower 3.1.9.2 with alpha =.05, power = 0.95, 2 groups and 4-time points. Using our between-group effect size for objective binge eating frequency (d=.98) future studies comparing EFT to a waitlist control group will need a minimum sample size of 12. However, if comparing individual EFT with an active psychotherapy (d=0.82; (58)) then future studies would require a minimum sample size of 320 participants to nd an effect. Using our betweengroup effect size for days without bingeing and loss of control (d=1.39) then future studies comparing EFT to a waitlist control group will need a minimum sample size of 8 participants. If comparing EFT with an active psychotherapy (d=1.04 (58)), then future studies will need a minimum of 70 participants to nd an effect.
The main limitation of the current research is the relatively small sample size which may limit the extent to which the sample is representative of people with binge eating disorder. Additionally, the majority of the sample was female and outcome measures were con ned to self-report measures which limited a participant's descriptions of attitudes and behaviors to those within their awareness. Furthermore, the secondary outcomes measures associated with anxiety and depression psychopathology were administered at pretherapy and follow-up only. Post-treatment follow-up at 16, 20 and 24 weeks was also relatively short, which limited the analysis of participant trajectory and capacity to maintain gains.
Finally,therapist effects cannot be ruled out given that the same therapist delivered the treatment, however, a recent investigation indicated that therapist effects account for only 5.8% of the variance in patient outcomes (e.g., 67).
The present study has several implications. Firstly, it provides further preliminary evidence that EFT may be an e cacious treatment for BED and builds upon previous ndings (e.g., 31,68). It also identi ed changes in objective binge episodes and days, binge eating psychopathology,and anxiety psychopathology that are theoretically important to EFT including emotion and emotion regulation. The dropout rate was also relatively low compared to other psychological therapy interventions for BED which indicates acceptability of the EFT intervention.

Conclusions
In conclusion, the evidence is emerging for the bene ts of EFT for BED which has a focus on assisting clients to experience and process unpleasant emotions and decreasing the reliance on an eating disorder as an emotional coping mechanism. Future research assessing EFT for BED needs to include a more extensive randomized control trial with a larger sample size to establish causal conclusions and equal gender representation to improve the generalizability of ndings. Consideration could also be given to a more extended follow-up period to improve the analysis of participant trajectory and capacity to maintain gains and the use of more than one therapist to rule out therapist effects.  Mean EDEQ and BES pretherapy, treatment and follow-up scores, and mean BAI and BDI pretherapy and follow-up scores (n=20)