Acceptance and Commitment Therapy for Adults Living With Inflammatory Bowel Disease and Distress: A Randomized Controlled Trial.

INTRODUCTION: The bidirectional relationship between disease activity and mental health in inflammatory bowel disease (IBD) has prompted investigations into the efficacy of psychotherapeutic interventions such as acceptance and commitment therapy (ACT) on biopsychosocial outcomes. We aimed to examine the efficacy of an ACT program (intervention) in comparison with a cognitive behavioral therapy-informed psychoeducation program (active control) for individuals with IBD and coexistent psychological distress. Both programs were delivered online through a hybrid format (i.e., therapist-led and participant-led sessions). METHODS: A total of 120 adults with IBD were randomized to either the intervention (N = 61) or active control groups (N = 59). Efficacy was determined using linear mixed models for group differences, in rate of changes in study outcomes, between baseline, postintervention, and 3-month follow-up. RESULTS: The primary outcome health-related quality of life significantly improved in the intervention group when compared with the active control group, with a significantly different rate of change observed from baseline to postintervention ( t [190] = 2.15, P = 0.033) in favor of the intervention group with a medium effect size (ß = 0.41, mean difference = 0.07, 95% confidence interval 0.01-0.12, P = 0.014). Similarly, the secondary outcome Crohn's disease activity significantly reduced in the intervention group when compared with the active control group, with a significantly different rate of change observed from baseline to 3-month follow-up ( t [90] = -2.40, P = 0.018) in favor of the intervention group with a large effect size (ß = -0.77, mean difference = -9.43, 95% confidence interval -13.72 to -5.13, P < 0.001) ( P = 0.014). Furthermore, when observing the rate of change in outcomes over time for the groups separately, anxiety symptoms and pain significantly improved in the intervention group only, and conversely, ulcerative colitis activity and stress symptoms significantly improved in the active control group only. All other outcomes (N = 14) significantly improved over time in both groups including IBD activity, gastrointestinal unhelpful thinking patterns, visceral anxiety, fatigue interference, fatigue severity, fatigue frequency, psychological inflexibility, self-efficacy, resilience, current health status, depression symptoms, IBD control, and pain catastrophizing; however, these changes were not significantly different between the groups. DISCUSSION: Both programs were of benefit to people with IBD and distress. However, ACT offers a significant added benefit for health-related quality of life and self-reported Crohn's disease activity and may be a useful adjuvant therapy in integrated IBD care.

Investigating change in network structure of eating disorder symptoms after delivery of a smartphone app-based intervention.

BACKGROUND: Eating disorder (ED) research has embraced a network perspective of psychopathology, which proposes that psychiatric disorders can be conceptualized as a complex system of interacting symptoms. However, existing intervention studies using the network perspective have failed to find that symptom reductions coincide with reductions in strength of associations among these symptoms. We propose that this may reflect failure of alignment between network theory and study design and analysis. We offer hypotheses for specific symptom associations expected to be disrupted by an app-based intervention, and test sensitivity of a range of statistical metrics for identifying this intervention-induced disruption. METHODS: Data were analyzed from individuals with recurrent binge eating who participated in a randomized controlled trial of a cognitive-behavioral smartphone application. Participants were categorized into one of three groups: waitlist (n = 155), intervention responder (n = 49), and intervention non-responder (n = 77). Several statistical tests (bivariate associations, network-derived strength statistics, network invariance tests) were compared in ability to identify change in network structure. RESULTS: Hypothesized disruption to specific symptom associations was observed through change in bivariate correlations from baseline to post-intervention among the responder group but were not evident from symptom and whole-of-network based network analysis statistics. Effects were masked when the intervention group was assessed together, ignoring heterogeneity in treatment responsiveness. CONCLUSION: Findings are consistent with our contention that study design and analytic approach influence the ability to test network theory predictions with fidelity. We conclude by offering key recommendations for future network theory-driven interventional studies.

Exploration of the individual and combined effects of predictors of engagement, dropout, and change from digital interventions for recurrent binge eating.

OBJECTIVE: Our ability to predict responsiveness to digital interventions for eating disorders has thus far been poor, potentially for three reasons: (1) there has been a narrow set of predictors explored; (2) prediction has mostly focused on symptom change, ignoring other aspects of the user journey (uptake, early engagement); and (3) there is an excessive focus on the unique effects of predictors rather than the combined contributions of a predictor set. We evaluated the univariate and multivariate effects of outcome predictors in the context of a randomized trial (n = 398) of digitally delivered interventions for recurrent binge eating. METHOD: Thirty baseline variables were selected as predictors, ranging from specific symptoms, to key protective factors, to technological acceptance, and to online treatment attitudes. Outcomes included uptake, early engagement, and remission. Univariate (d) and multivariate (D) standardized mean differences were calculated to estimate the individual and combined effects of predictors, respectively. RESULTS: At the univariate level, few predictors produced an effect size larger than what is considered small (d > .20) across outcomes. However, our multivariate approach enhanced prediction (Ds = .65 to 1.12), producing accuracy rates greater than chance (63%-71% accuracy). Less than half of the chosen variables proved to be useful in contributing to predictions in multivariate models. CONCLUSION: Findings suggest that accuracy in outcome prediction from digitally delivered interventions may be better driven by the aggregation of many small effects rather than one or several largely influential predictors. Replication with different data streams (sensor, neuroimaging) would be useful. PUBLIC SIGNIFICANCE: Our ability to predict who will and will not benefit from digital interventions for eating disorders has been poor. We highlight the viability of a multivariate approach to outcome prediction, whereby prediction may be better driven by the aggregation of many small effects rather than one or a few influential predictors.

Resilience eDBT: Development and Usability Evaluation of a Dialectical Behavior Therapy Skills Training App for Eating Disorders.

OBJECTIVE: Dialectical behavior therapy (DBT) is an evidence-based treatment for disorders characterized by recurrent binge eating. Yet, access to specialized treatment like DBT remains limited. To increase the accessibility of DBT, we developed a DBT skills training app (Resilience: eDBT) for the management of eating disorder (ED) symptoms. This paper delineates the developmental process of Resilience and tests its usability. METHODS: Descriptive information on the development and features of Resilience is provided, including its framework, content structure and delivery formats, functionality, data storage procedure, and privacy protocols. Usability was assessed via a mixed methods approach in 10 symptomatic individuals. Qualitative data were organized based on an existing framework, which included six themes: usability, visual design, user engagement, content, therapeutic persuasiveness, and therapeutic alliance. RESULTS: Resilience demonstrated good usability via a Systems Usability Scale score of 85.5, which exceeded the recommended cutoff of 68. Positive aspects of the app, according to interview data, were the ease of use and the visual design, while the addition of peer support was suggested as an opportunity for improvement. DISCUSSION: A novel DBT-based app may serve as an acceptable, low-intensity option or adjunct to traditional treatment for targeting ED symptoms that emerge in daily life. However, notable limitations include the small sample size and the single time point at which the usability assessment was conducted.

Exploring longitudinal relationships between fitness tracking and disordered eating outcomes in college-aged women.

OBJECTIVE: A growing body of research, primarily cross-sectional, suggests a relationship between the practice of tracking one's food intake and exercise behaviors using fitness-tracking smartphone applications ("apps") or wearable devices ("wearables") and disordered eating symptomatology. The aim of the present study was to explore longitudinal relationships between fitness tracking and disordered eating outcomes among college-aged women, as well as to determine whether the individual-level risk factors of pre-existing eating concerns, perfectionism, and rumination about food moderated the relationship. METHOD: N = 68 female undergraduates used the MyFitnessPal app for 8 weeks while completing a series of self-report measures. RESULTS: At the trait level, fitness tracking frequency was positively associated with weight/shape concerns, but not with the other outcome measures. Daily levels of fitness tracking did not predict next-day levels for any of the outcome measures. Within-day fitness tracking at one timepoint was associated with lower reports of dietary restraint efforts at the next timepoint. None of the proposed moderators significantly interacted with the relationships over time. DISCUSSION: These results suggest that while those who engage in fitness tracking may experience higher weight/shape concerns as a trait, over time fitness tracking was not associated with an increase in concerns. Further work exploring whether fitness tracking may affect particular subgroups in different ways is warranted.

A randomized controlled trial of an online single session intervention for body image in individuals with recurrent binge eating.

OBJECTIVE: Theoretical models highlight body image disturbances as central to the maintenance of eating disorders, with empirical evidence finding negative body image to be a robust predictor of treatment nonresponse, relapse and symptom persistence. Accessible, scalable, and inexpensive interventions that can effectively target negative body image across the eating disorders are needed. We developed an online single session intervention (SSI) for negative body image and evaluated its acceptability and efficacy in a randomized controlled trial in individuals with recurrent binge eating. METHOD: Participants with recurrent binge eating were randomly assigned to the SSI (n = 99) or a waitlist (n = 101). Assessments were conducted at baseline, 4 week follow-up, and 8 week follow-up. RESULTS: 81% of participants accessed the SSI, demonstrating reasonable uptake. However, issues with attrition were apparent; a 32% study dropout rate was observed at posttest, while a 58% dropout rate was observed at follow-up. 87% of participants who completed satisfaction measures would recommend the SSI. SSI participants experienced greater improvements in negative body image at both 4 (d = -0.65) and 8 week (d = -0.74) follow-up. Significant between-group effects were also observed on most other secondary symptom measures, though no differences were found for motivations and help-seeking beliefs and intentions. CONCLUSION: Body image-focused self-guided SSIs for recurrent binge are largely accepted by those who are retained in the trial, but are associated with significant attrition. Although SSIs are not intended to replace standard treatment, they may help with short-term symptom management and could play an important role in eating disorder care. PUBLIC SIGNIFICANCE: Single session interventions (SSI) are a potentially accessible, scalable, and cost-effective way to deliver evidence-based treatment content to people with eating disorders. This study shows that an online (SSI) designed to target body image among people with recurrent binge eating is accepted and produced short-term symptom relief.

People with Inflammatory Bowel Disease Prefer Cognitive Behavioral Therapy for Fatigue Management: A Conjoint Analysis.

BACKGROUND: Psychological interventions are a promising area for fatigue management in patients with inflammatory bowel disease (IBD). However, most interventions trialled to date have been pilots with limited direct input from patients about the type of intervention they want. Thus, this study aimed to explore patient preferences for a psychological IBD fatigue intervention. METHODS: An international online cross-sectional survey was conducted with adults with self-reported IBD. A conjoint analysis was employed to elicit, through a series of forced-choice scenarios, patient preferences for a fatigue intervention. For this study, the attributes manipulated across these forced-choice scenarios were type of intervention, modality of delivery, and duration of intervention. RESULTS: Overall, 834 people with IBD were included in analysis. Respondents ranked the type of psychological intervention as most important for overall preference (with cognitive-behavioral therapy (CBT) preferred over the other approaches), followed by modality of delivery, but placed very little importance on how long the intervention runs for. Patients with IBD appear to most strongly preference a short online CBT intervention for managing their IBD-related fatigue. CONCLUSION: This study helps provide therapists and program developers clear direction on patient preferences when it comes to developing new psychological programs that address fatigue in IBD.

Taking a Deeper Dive Into OSFED Subtypes: A Meta-Analysis and Systematic Review.

OBJECTIVE: To compare all other specified feeding or eating disorders (OSFED) groups (atypical anorexia nervosa [AN], purging disorder [PD], night eating syndrome [NES], subthreshold bulimia nervosa [sub-BN], and subthreshold binge-eating disorder [sub-BED]) to threshold eating disorders (EDs [AN, BN, and BED]) and control groups (CGs) on measures of eating and general psychopathology. METHOD: We conducted a comprehensive search in PsycINFO, Medline, Embase, and CINAHL on all published studies from January 2013 to February 2024 using DSM-5 diagnostic criteria via clinical interviews or well-established diagnostic tools. We also undertook a quality appraisal using an adapted version of the Downs and Black criteria and registered the review with PROSPERO (ID: CRD42022314495). RESULTS: Overall, our meta-analyses (n = 33 eligible studies) indicated that the combined OSFED and several specific OSFED subtypes displayed comparable levels of eating psychopathology to full-threshold EDs. Our systematic review (n = 33 eligible studies) found individuals with OSFED to have comparable levels of eating and general psychopathology to full-threshold EDs, but higher levels of eating and general psychopathology than CGs. These findings were specifically attributed to atypical AN and NES. There was a lack of evidence available for sub-BN and sub-BED. Studies mainly met the quality appraisal criteria. The main limitations identified in the included studies were insufficient reporting of their statistical power (78%) and no adjusting for potential confounding factors (67%). DISCUSSION: Findings support the conceptualization of atypical AN, and NES as clinically significant EDs with similar severity to full-threshold EDs.

Overlap of eating disorders and neurodivergence: the role of inhibitory control.

BACKGROUND: Difficulties with inhibitory control have been identified in eating disorders (EDs) and neurodevelopmental disorders (NDs; including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder), and there appear to be parallels between the expression of these impairments. It is theorised that impairments in inhibitory control within NDs may represent a unique vulnerability for eating disorders (EDs), and this same mechanism may contribute to poorer treatment outcomes. This review seeks to determine the state of the literature concerning the role of inhibitory control in the overlap of EDs and neurodivergence. METHOD: A scoping review was conducted to summarise extant research, and to identify gaps in the existing knowledge base. Scopus, Medline, PsycInfo, Embase, and ProQuest were systematically searched. Studies were included if the study measured traits of ADHD or autism, and symptoms of ED, and required participants to complete a performance task measure of inhibitory control. Where studies included a cohort with both an ND and ED, these results had to be reported separately from cohorts with a singular diagnosis. Studies were required to be published in English, within the last 10 years. RESULTS: No studies explored the relationship between autism and EDs using behavioural measures of inhibitory control. Four studies exploring the relationship between ADHD and EDs using behavioural measures of inhibitory control met selection criteria. These studies showed a multifaceted relationship between these conditions, with differences emerging between domains of inhibitory control. ADHD symptoms predicted poorer performance on measures of response inhibition in a non-clinical sample; this was not replicated in clinical samples, nor was there a significant association with EDs. Both ADHD and ED symptoms are associated with poor performance on attentional control measures; where these diagnoses were combined, performance was worse than for those with a singular diagnosis of ADHD. This was not replicated when compared to those with only ED diagnoses. CONCLUSION: Impairments in attentional control may represent a unique vulnerability for the development of an ED and contribute to poor treatment outcomes. Further research is needed to explore the role of inhibitory control in EDs, ADHD and autism, including the use of both self-report and behavioural measures to capture the domains of inhibitory control.

The Intuitive Eating Scale-3: Development and psychometric evaluation.

Intuitive eating has been found to protect against disordered eating and preserve well-being. Yet, there are methodological (length), conceptual (inconsideration of medical, value-based, and access-related reasons for food consumption), and psychometric (item wording) concerns with its most common measure, the Intuitive Eating Scale-2 (IES-2). To address these concerns, we developed the IES-3 and investigated its psychometric properties with U.S. community adults. Across three online studies, we evaluated the IES-3's factorial validity using exploratory factor analysis (EFA; Study 1; N = 957; Mage = 36.30), as well as confirmatory factor analysis (CFA), exploratory structural equation modeling (ESEM), bifactor-CFA, and bifactor-ESEM (Study 2; N = 1152; Mage = 40.95), and cross-validated the optimal model (Study 3; N = 884; Mage = 38.54). We examined measurement invariance across samples and time, differential item functioning (age, body mass index [BMI], gender), composite reliability, and validity. Study 1 revealed a 12-item, 4-factor structure (unconditional permission to eat, eating for physical reasons, reliance on hunger and satiety cues, body-food choice congruence). In Study 2, a bifactor-ESEM model with a global intuitive eating factor and four specific factors best fit the data, which was temporally stable across three weeks. This model also had good fit in Study 3 and, across Studies 2 and 3, and was fully invariant and lacked measurement bias in terms of age, gender, and BMI. Associations between latent IES-3 factors and age, gender, and BMI were invariant across Studies 2 and 3. Composite reliability and validity (relationships with disordered eating, embodiment, body image, well-being, and distress; negligible relationship with impression management) of the retained model were also supported. The 12-item IES-3 demonstrates strong psychometric properties in U.S. community adults. Research is now needed using the IES-3 in other cultural contexts and social identity groups.

A new network analysis model in anorexia nervosa patients based on self-reported eating disorder symptoms, psychological distress, and cognitive flexibility.

OBJECTIVES: Cognitive flexibility and psychological distress, such as depression and anxiety, have been implicated in the aetiology of Anorexia Nervosa (AN). Despite the known associations between eating disorder (ED) symptoms, depression, anxiety, and cognitive flexibility, the specific pathways that connect these constructs are unclear. We therefore used network analysis to examine the relationship between these symptoms in an AN sample. METHODS: One hundred and ninety-three treatment-seeking individuals diagnosed with AN (95.6% female, M = 26.89 [SD = 9.45] years old) completed self-report measures assessing depression, anxiety, cognitive flexibility, and ED symptoms. To determine each symptom's influence in the network, we calculated the expected influence. RESULTS: The two relationships with the greatest edges were those between (1) weight/shape concerns and eating/dietary restraint and (2) weight/shape concerns and psychological distress (a measure that combined depression and anxiety). Cognitive flexibility was not connected to weight/shape concerns but had negative partial associations with eating concerns/dietary restraint and psychological distress. There was also a slight, non-zero connection between eating concerns/dietary restraint and psychological distress. CONCLUSIONS: The findings underscore the importance of weight/shape, eating/dietary concerns, and psychological distress in the AN network and suggest that addressing cognitive flexibility may be a useful target for eating concerns/dietary restraint and psychological distress. Future studies assessing the longitudinal course of psychopathology within the AN network structure may help in identifying whether specific symptoms function as risk factors or maintaining factors for this co-occurrence.

Effects of videoconferencing use on momentary changes in disordered eating urges, body dissatisfaction, and mood.

The coronavirus disease 2019 (COVID-19) pandemic led to a global surge in videoconferencing use for work/study-related reasons. Although these platforms heighten exposure to one's image, the implications of videoconferencing use on body image and eating concerns remain scantly examined. This study sought to investigate, in an Australian sample, whether videoconferencing for work/study-related reasons predicted increases in body dissatisfaction (BD), urge to engage in disordered eating (DE; restrictive eating, exercise, overeating/purging), and negative mood at the state level. Participants (N = 482, 78.8% women, Mage  = 20.5 years [SD = 5.3]) completed baseline demographic measures, accompanied by an ecological momentary assessment (EMA) of videoconferencing for work/study-related reasons, BD, DE urges, and negative mood six times a day for 7 days via a smartphone application. Most participants (n = 429; 89.0%) reported state-based videoconferencing use during the EMA phase. Consistent with expectations, state-based videoconferencing use was associated with an increase in state-level urges to engage in exercise. However, contrary to predictions, state-based videoconferencing use was linked to a decrease in state-level BD at the next assessment point and failed to predict negative mood and urges to engage in restrictive eating or overeating/purging at the state level. Given the simplified measure of videoconferencing use, the current research is considered preliminary and future replication and extension, using more nuanced measures, is warranted.

Validating and developing a shortened version of the detail and flexibility (DFlex) questionnaire for eating disorders, anxiety and depression.

OBJECTIVE: To validate the original and a shortened version of the Detail and Flexibility (DFlex) Questionnaire. METHOD: Confirmatory factor analyses, internal consistency, and discriminant validity estimates were conducted within individuals with a diagnosis of an eating disorder (ED) (n = 124), an anxiety disorder and/or depression (n = 219), and a community sample (n = 852) (Part 1). Convergent validity of the DFlex through comparisons with the Autism Spectrum Quotient, Wisconsin Card Sorting Task, and Group Embedded Figures Task was undertaken within a combined ED and community sample (N = 68). Test-retest reliability of the DFlex was also examined across 2 years in a community sample (N = 85) (Part 2). RESULTS: The original factor structure of the DFlex was not supported. Hence, a shortened version, the DFlex-Revised, was developed. Good discriminant validity was obtained for the DFlex and DFlex-Revised, however, support for convergent validity was mixed. Finally, the 2-year test-retest reliability for the two DFlex versions was found to be low, suggesting potential malleability in construct over this timeframe. CONCLUSIONS: Further research is needed to validate the DFlex in clinical and non-clinical populations using different neurocognitive tests. Test-retest, using varied time intervals, should also be assessed.

Moving Towards Acceptance and Values: A Qualitative Study of ACTforIBD Compared to IBD Psychoeducation.

The current study explored perspectives of those with inflammatory bowel disease (IBD) and comorbid anxiety and/or depression on a hybrid acceptance and committment therapy (ACT) intervention, compared to an active control. This qualitative study was nested within a randomized controlled trial (RCT) where an experimental group received an 8-week blended delivery ACTforIBD intervention (four sessions telehealth, four sessions pre-recorded self-directed), while an active control group received a psychoeducation program of similar intensity. Semi-structured interviews were conducted post-intervention and at a 3-month follow-up. Themes were interpreted using reflexive thematic analysis. Twenty individuals participated; ten in each condition. Seven themes were constructed, including three shared themes between groups: I Am Worth Advocating For, Present Moment Is My Biggest Ally, and Ambivalence About Self-Directed Modules. Two themes were identified for the ACTforIBD group: Symptoms Are Going to Happen and Moving Toward Values while two themes identified from the ActiveControl group were: Reset and Refresh and It's Ok to Say No. Acceptance and values modules from ACTforIBD were perceived as useful in reducing psychological distress for those with IBD, while the ActiveControl group felt their program affirmed existing effective coping strategies. Access to external resources for self-directed modules and networking may increase engagement with content long term.

Target-user preferences, motivations, and acceptance for a dialectical behaviour therapy smartphone application for eating disorders.

PURPOSE: Evidence shows that dialectical behavioural therapy (DBT) is efficacious for eating disorders (ED), yet few people have access to specialized treatments like DBT. Translating key DBT skills for delivery via a smartphone application may broaden the dissemination of evidence-based interventions. However, prior to developing a DBT-based app, it is crucial to gather information on target-user needs and preferences. Assessing overall acceptance and identifying predictors of acceptance, informed by the UTAUT framework, is also important. This process ensures not only a demand for such an app, but also that users receive content and features tailored to their needs. METHOD: This study aimed to understand target-user preferences of DBT-based apps for EDs by assessing willingness to engage, overall acceptance levels, and preferred functionality/content delivery modes (n = 326 symptomatic participants). RESULTS: Eighty-eight percent indicated they would be willing to use a DBT-based ED app if it were available. Acceptance levels of a DBT app were high (64%), which was uniquely predicted by performance expectancy (perceptions of how beneficial an intervention is) and facilitating conditions (expectations of technological infrastructure and support in interventions) in path analysis. Content perceived as important to contain were emotion regulation techniques, tailored intervention strategies, and psychoeducation. CONCLUSION: Findings generate important information about target-user preferences of a DBT-based app for EDs, highlighting necessary design principles for apps of this kind. Level of evidence Level V, cross-sectional descriptive study.

A broad v. focused digital intervention for recurrent binge eating: a randomized controlled non-inferiority trial.

BACKGROUND: Empirically validated digital interventions for recurrent binge eating typically target numerous hypothesized change mechanisms via the delivery of different modules, skills, and techniques. Emerging evidence suggests that interventions designed to target and isolate one key change mechanism may also produce meaningful change in core symptoms. Although both 'broad' and 'focused' digital programs have demonstrated efficacy, no study has performed a direct, head-to-head comparison of the two approaches. We addressed this through a randomized non-inferiority trial. METHOD: Participants with recurrent binge eating were randomly assigned to a broad (n = 199) or focused digital intervention (n = 199), or a waitlist (n = 202). The broad program targeted dietary restraint, mood intolerance, and body image disturbances, while the focused program exclusively targeted dietary restraint. Primary outcomes were eating disorder psychopathology and binge eating frequency. RESULTS: In intention-to-treat analyses, both intervention groups reported greater improvements in primary and secondary outcomes than the waitlist, which were sustained at an 8-week follow-up. The focused intervention was not inferior to the broad intervention on all but one outcome, but was associated with higher rates of attrition and non-compliance. CONCLUSION: Focused digital interventions that are designed to target one key change mechanism may produce comparable symptom improvements to broader digital interventions, but appear to be associated with lower engagement.

Targeting dietary restraint to reduce binge eating: a randomised controlled trial of a blended internet- and smartphone app-based intervention.

BACKGROUND: Existing internet-based prevention and treatment programmes for binge eating are composed of multiple distinct modules that are designed to target a broad range of risk or maintaining factors. Such multi-modular programmes (1) may be unnecessarily long for those who do not require a full course of intervention and (2) make it difficult to distinguish those techniques that are effective from those that are redundant. Since dietary restraint is a well-replicated risk and maintaining factor for binge eating, we developed an internet- and app-based intervention composed solely of cognitive-behavioural techniques designed to modify dietary restraint as a mechanism to target binge eating. We tested the efficacy of this combined selective and indicated prevention programme in 403 participants, most of whom were highly symptomatic (90% reported binge eating once per week). METHOD: Participants were randomly assigned to the internet intervention (n = 201) or an informational control group (n = 202). The primary outcome was objective binge-eating frequency. Secondary outcomes were indices of dietary restraint, shape, weight, and eating concerns, subjective binge eating, disinhibition, and psychological distress. Analyses were intention-to-treat. RESULTS: Intervention participants reported greater reductions in objective binge-eating episodes compared to the control group at post-test (small effect size). Significant effects were also observed on each of the secondary outcomes (small to large effect sizes). Improvements were sustained at 8 week follow-up. CONCLUSIONS: Highly focused digital interventions that target one central risk/maintaining factor may be sufficient to induce meaningful change in core eating disorder symptoms.

The promise of single session interventions for eating disorders: Lessons to be learned from research on digital mental health. Commentary on Schleider et al. (2023).

Schleider et al. propose that single session interventions (SSIs) could be a promising path toward catalyzing innovation in the development of accessible interventions for eating disorders (EDs). In this commentary, we contend that the arguments made by Schleider et al. raise many unresolved questions that continue to arise in the broader field. Drawing from our experiences with-and lessons learned from-developing, evaluating, and disseminating digital health interventions, we discuss four key empirical questions that should be addressed in order to realize the full potential of SSIs and other innovations in intervention delivery. These include: (i) for whom do we deliver an SSI; (ii) what are the optimal treatment mechanisms to target; (iii) what constitutes a "good" outcome; and (iv) where and how might we embed innovations like these. The SSI approach is a fruitful area of research enquiry, and we hope that this commentary generates further discussion and high-quality, collaborative work related to improving treatment accessibility and clinical outcomes among people with EDs.

A meta-analytic review of impact of measurement choice on RCTs to reduce appearance internalization.

OBJECTIVE: Prior reviews have shown that interventions targeting internalization of appearance standards are generally efficacious, though there is considerable heterogeneity in estimates across studies. This updated review of the literature evaluates whether efficacy estimates from RCTs systematically vary as a function of three related outcome measures (internalization, awareness, and perceived pressure regarding appearance standards). METHODS: Seven electronic databases were systematically searched from inception to February 8, 2023. The Cochrane Risk of Bias tool assessed each study's risk of bias. Studies included were randomized-controlled trials evaluating body image/eating disorder prevention or intervention programs targeting internalization as a focal point of treatment. Effect sizes were meta-analyzed and meta-regression analyses were conducted investigating the impact of outcome measure choice on study effect size at post-intervention and follow-up. RESULTS: Thirty-seven studies (N = 4809 participants) were included. The meta-analytic findings as expected found interventions efficacious at reducing internalization post-intervention (d = -0.47, 95% CI [-0.60 to -0.34], k = 44), and at follow-up (d = -0.28, 95% CI [-0.39 to -0.17], k = 43), but also highly heterogenous (I2 = 52-67%). Operationalization of internalization moderated results at follow-up but not post-intervention timepoints, with awareness measures (compared with internalization measures) producing weaker effect sizes. Exploratory analyses found bigger effects when internalization was compared with all other measurement categories combined, suggesting possible issues with statistical power in main analyses. DISCUSSION: Mixed present findings suggest need for further evaluation of measurement effects on efficacy, and possible caution in choice of outcome measure for internalization-based interventions. PUBLIC SIGNIFICANCE STATEMENT: This review provides some preliminary evidence that choice of survey measures used in randomized controlled trials can impact our judgments about whether a trial reduces the extent to which participants endorse unrealistic appearance standards. Accuracy in measurement of this efficacy of trials is crucial, given the role that internalized appearance standards play in onset and maintenance of eating disorders.

OBJETIVO: Las revisiones anteriores han demostrado que las intervenciones dirigidas a la internalización de los estándares de apariencia son generalmente eficaces, aunque existe una heterogeneidad considerable en las estimaciones entre los estudios. Esta revisión actualizada de la bibliografía evalúa si las estimaciones de eficacia de los ECA varían sistemáticamente en función de tres medidas de resultado relacionadas (internalización, conciencia y presión percibida con respecto a los estándares de apariencia). MÉTODO: Se realizaron búsquedas sistemáticas en siete bases de datos electrónicas desde su inicio hasta el 8 de febrero de 2023. La herramienta Cochrane Risk of Bias evaluó el riesgo de sesgo de cada estudio. Los estudios incluidos fueron ensayos controlados aleatorios (ECA) que evaluaron la prevención de la imagen corporal/trastornos alimentarios o programas de intervención dirigidos a la internalización como punto focal del tratamiento. Se metanalizaron los tamaños del efecto y se realizaron análisis de metarregresión que investigaron la repercusión de la elección de la medida de resultado sobre el tamaño del efecto del estudio después de la intervención y el seguimiento. RESULTADOS: Se incluyeron treinta y siete estudios (N = 4 809 participantes). Los hallazgos metaanalíticos como era de esperarse encontraron intervenciones eficaces para reducir la internalización después de la intervención (d = -0,47, IC del 95% [-0,60 a -0,34], k = 44) y en el seguimiento (d = -0,28, IC del 95% [-0,39 a -0,17], k = 43), pero también altamente heterogéneas (I2 = 52-67%). La operacionalización de la internalización moderó los resultados en los puntos temporales de seguimiento pero no en posteriores a la intervención, y las medidas de sensibilización (en comparación con las medidas de internalización) produjeron tamaños del efecto más débiles. Los análisis exploratorios encontraron mayores efectos cuando la internalización se comparó con todas las demás categorías de medición combinadas, lo que sugiere posibles problemas con el poder estadístico en los análisis principales. DISCUSIÓN: Los hallazgos actuales mixtos sugieren la necesidad de una evaluación adicional de los efectos de la medición sobre la eficacia, y la posible precaución en la elección de la medida de resultado para las intervenciones basadas en la internalización.

Predictors, mediators, and moderators of response to digital interventions for eating disorders: A systematic review.

OBJECTIVE: Digital interventions show promise as an effective prevention or self-management option for eating disorders (EDs). However, it remains unclear how, for whom, and through what mechanisms they work in this population, as a synthesis of outcome predictors, moderators, and mediators is lacking. This systematic review synthesized empirical research investigating predictors, mediators, and moderators of response to digital interventions for EDs. METHOD: Six databases were searched (PROSPERO CRD42022295565) for studies that assessed predictors, moderators, or mediators of response (i.e., uptake, drop-out, engagement, and symptom level change) to a digital prevention or treatment program for EDs. Variables were grouped into several overarching categories (demographic, symptom severity, psychological, etc.) and were synthesized qualitatively across samples without a formally diagnosed ED (typically prevention-focused) and samples with a formally diagnosed ED (typically treatment-focused). RESULTS: Eighty-six studies were included. For studies recruiting samples without a formal diagnosis (n = 70 studies), most predictors explored were statistically unrelated to outcome, although participant age, baseline symptom severity, confidence to change, motivation, and program engagement showed preliminary evidence of prognostic potential. No robust moderators or mediators were identified. Few studies recruiting samples with a formal diagnosis emerged (n = 16), of which no reliable predictors, moderators, or mediators were identified. DISCUSSION: It remains unclear how, for whom, and under what circumstances digital programs targeting EDs work. We offer several recommendations for future research with the aim of advancing understanding of client characteristics and intervention elements that signal success from this intervention modality. PUBLIC SIGNIFICANCE: Digital interventions have shown potential as an effective, scalable, and accessible intervention option for EDs. However, responsiveness varies, so advancing understanding of predictors, mediators, and moderators of outcome to digital interventions for EDs is needed. Such knowledge is important for enabling safe and efficient treatment matching, and for informing future development of effective digital interventions.

OBJETIVO: Las intervenciones digitales se muestran prometedoras como una opción eficaz de prevención o autocontrol de los trastornos de la conducta alimentaria (TCA). Sin embargo, sigue sin estar claro cómo, para quién y a través de qué mecanismos funcionan en esta población, ya que falta una síntesis de los predictores de resultados, moderadores y mediadores. Esta revisión sistemática sintetiza la investigación empírica que estudia los predictores, mediadores y moderadores de la respuesta a las intervenciones digitales para los TCA. MÉTODO: Se realizaron búsquedas en seis bases de datos (CRD42022295565) de estudios que evaluaron predictores, moderadores o mediadores de la respuesta (es decir, admisión, abandono, compromiso y cambio en el nivel de síntomas) a un programa digital de prevención o tratamiento de los TCA. Las variables se agruparon en varias categorías generales (demográficas, gravedad de los síntomas, psicológicas, etc.) y se sintetizaron cualitativamente en muestras sin un TCA diagnosticado formalmente (normalmente centradas en la prevención) y muestras con un TCA diagnosticado formalmente (normalmente centradas en el tratamiento). RESULTADOS: Se incluyeron 86 estudios. Para los estudios que reclutaron muestras sin un diagnóstico formal (n = 70 estudios), la mayoría de los predictores explorados no estaban estadísticamente relacionados con el resultado, aunque la edad del participante, la gravedad de los síntomas basales, la confianza en el cambio, la motivación y el compromiso con el programa mostraron evidencia preliminar de potencial pronóstico. No se identificaron moderadores o mediadores sólidos. Surgieron pocos estudios que reclutaran muestras con un diagnóstico formal (n = 16), de los cuales no se identificaron predictores, moderadores o mediadores fiables. DISCUSIÓN: Sigue sin estar claro cómo, para quién y en qué circunstancias funcionan los programas digitales dirigidos a los TCA. Ofrecemos varias recomendaciones para futuras investigaciones con el objetivo de avanzar en la comprensión de las características de los consultantes y los elementos de intervención que señalan el éxito de esta modalidad de intervención.