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.

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.

Cognitive and emotional empathy in acute and remitted anorexia nervosa: a systematic review.

Background: Impairments in empathy are well established in anorexia nervosa (AN). It is unclear, however, whether these deficits only occur in the acute phases of AN due to neurocognitive impacts of starvation (often referred to as context-dependent, or state-like), or if deficits remain once remission has been achieved (trait-like). This debate is commonly referred to as the 'state vs trait' debate. Objective: This systematic review aims to summarise existing literature regarding empathy in AN, and to investigate whether empathy deficits in AN are state- or trait-based. Method: A total of 1014 articles were identified, and seven articles remained after the screening process. These seven articles, comparing empathy across three groups (acute AN, remission of AN, and non-clinical controls), were evaluated and summarised in accordance with PRISMA guidelines. Articles were required to have included all three groups and report on either cognitive empathy and/or emotional empathy. Results: The majority of studies were of satisfactory quality. The results identified were inconsistent, with few articles lending some support to the 'state' hypothesis and others producing nonsignificant results. Conclusions: There is minimal literature comparing empathy in acute and remission phases of AN. While there were some inconsistencies in included articles, some data indicate that there may be slight improvements to emotional and cognitive empathy following recovery of AN. Further research is needed to better enrich knowledge regarding the role of state vs trait with regard to neurocognitive difficulties experienced by individuals with AN. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=335669, identifier CRD42022335669.

An ecological momentary assessment of OCD-relevant intrusions: Frequency, feared self, and concealment.

This study provides the first examination of the frequency, characteristics, and dynamics surrounding daily experiences of OCD-relevant intrusions among non-clinical participants (N = 54, Nobs = 2314) using ecological momentary assessment. It also examines the extent to which self-related constructs-participants' feared-self beliefs and their tendency to conceal aspects of self-relate to such intrusive phenomena. Participants completed a baseline questionnaire before reporting state depressed mood and intrusions up to five times per day (at semi-random intervals) for 14 days. Results suggest that questionnaire measures may result in underreporting of the frequency of intrusions, with most participants (80%) reporting at least one intrusion across the momentary observations, and 20% of observations indicating intrusive phenomena experienced since the previous momentary report. Baseline factors including OCD-related beliefs and feared self were related to the proportion of intrusions experienced, whereas self-concealment was not. Within the moment, state feared-self predicted intrusion-related distress, duration, perceived importance, the urge to act, and the need to control thoughts. The urge to conceal within the moment was significant but negatively related to perceived importance and the urge to act. Overall, this study provides evidence for the relevance of momentary measures of intrusions, and adds to evidence for self-beliefs in the dynamics of the disorder.

The impact of oxytocin on emotion recognition and trust: Does disordered eating moderate these relationships?

OBJECTIVES: The current study aimed to investigate the impact of oxytocin on emotion recognition, trust, body image, affect, and anxiety and whether eating disorder (ED) symptoms moderated any of these relationships. METHOD: Participants (n = 149) were female university students, who were randomly allocated to receive in a double-blind nature, a single dose of oxytocin intranasal spray (n = 76) or a placebo (saline) intranasal spray (n = 73). Participants were asked to complete an experimental measure of emotion recognition and an investor task aimed to assess trust. RESULTS: The oxytocin group exhibited better overall performance on the emotion recognition task (especially with recognising positive emotions), and a decline in state positive affect than the control group at post-intervention. However, these effects were not moderated by ED symptom severity, nor were effects found for state anxiety, negative affect, body image and recognising negative emotions in the emotion recognition task. CONCLUSION: The current findings contribute to the growing literature on oxytocin, emotion recognition and positive affect and suggest that ED pathology does not moderate these relationships. Future research would benefit from examining the efficacy of an oxytocin intervention using a within-subjects, cross-over design, in those with sub-clinical and clinical EDs, as well as healthy controls.

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.

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.

Enhancing inferences and conclusions in body image focused non-experimental research via a causal modelling approach: A tutorial.

Causal inference is often the goal of psychological research. However, most researchers refrain from drawing causal conclusions based on non-experimental evidence. Despite the challenges associated with producing causal evidence from non-experimental data, it is crucial to address causal questions directly rather than avoiding them. Here we provide a clear, non-technical overview of the fundamental concepts (including the counterfactual framework and related assumptions) and tools that permit causal inference in non-experimental data, intended as a starting point for readers unfamiliar with the literature. Certain tools, such as the target trial framework and causal diagrams, have been developed to assist with the identification and reduction of potential biases in study design and analysis and the interpretation of findings. We apply these concepts and tools to a motivating example from the body image field. We assert that more precise and detailed elucidation of the barriers to causal inference within one's study is arguably a key first step in the enhancement of non-experimental research and future intervention development and evaluation.

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.

Improving usual care outcomes in major depression in youth by targeting memory specificity: A randomized controlled trial of adjunct computerized memory specificity training (c-MeST).

OBJECTIVE: Extending on previous findings that computerized Memory Specificity Training (c-MeST) improves memory specificity and depressive symptoms in Major Depressive Disorder (MDD) in adults, this study aimed to assess the effects of c-MeST in youth with MDD on memory specificity and depression in addition to other treatment. METHODS: Participants aged 15-25 (N = 359, 76 % female; M age = 19.2, SD = 3.1), receiving predominantly psychological therapy or counseling (85 %) and/or antidepressants (52 %) were randomized to usual care and c-MeST or usual care. Cognitive and clinical outcomes were assessed at baseline and at one, three, and six-month follow-ups. RESULTS: The usual care and c-MeST group reported higher memory specificity at one-month (d = 0.42, p = .022), but not at three or six months (d's < 0.15, p's > 0.05). The rate of MDE was numerically lower in the c-MeST group at each follow-up time-point, but group was not a statistically significant predictor at one month (64 % usual care and c-MeST vs. 68 % usual care, OR = 0.81, p = .606), three months (67 % usual care and c-MeST vs. 72 % usual care, OR = 0.64, p = .327) or six months (55 % usual care and c-MeST vs. 68 % usual care, OR = 0.56, p = .266). The usual care and c-MeST group did report lower depressive symptoms at one month (d = 0.42, p = .023) and six-months (d = 0.84, p = .001), but not three-months (d = 0.13, p > .05). CONCLUSIONS: c-MeST may reduce symptoms in youth with MDD when provided alongside other treatments. However, there are significant limitations to this inference, including high attrition in the study and a need for more data on the acceptability of the intervention.

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.

The Connection Between Sleep Problems and Emotional and Behavioural Difficulties in Autistic Children: A Network Analysis.

The interactions between sleep problems, autism symptoms and emotional and behavioural difficulties were explored using network analysis in 240 autistic children (mean age: 8.8 years, range 5-13 years) with moderate to severe sleep problems. Findings revealed a highly connected and interpretable network, with three separate clusters identified of the modelled variables. Depression, anxiety and behavioural difficulties were the most central variables of the network. Depression, anxiety and restricted repetitive and stereotyped patterns behaviours (RRBs) were the strongest bridging variables in the network model, transmitting activation both within and between other symptom clusters. The results highlight that depression and anxiety were highly connected symptoms within the network, suggesting support in these areas could be helpful, as well as future research.

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.

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.

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.

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.

Attentional engagement with and disengagement from appearance ideals: Differential associations with body dissatisfaction frequency and duration?

Recent work has served to dissociate two dimensions of trait body dissatisfaction: body dissatisfaction frequency and body dissatisfaction duration. The present study sought to evaluate whether body dissatisfaction frequency and body dissatisfaction duration are each associated with distinct patterns of appearance-related cognitive processing. It was hypothesized that speeded attentional engagement with idealized bodies is associated with higher frequency of body dissatisfaction episodes, while slowed attentional disengagement from such information may instead be associated with higher duration of body dissatisfaction episodes. Participants (238 women, 149 men) completed an attentional task capable of independently assessing attentional engagement with, and attentional disengagement from, idealized bodies. Participants also completed both trait and in vivo (i.e., ecological momentary assessment) measures of body dissatisfaction frequency and duration. Results showed that neither engagement nor disengagement bias index scores predicted variance in either body dissatisfaction frequency measures or body dissatisfaction duration measures. Findings suggest that either biased attentional engagement with, and disengagement from, idealized bodies do not associate with the frequency and duration of body dissatisfaction episodes, or there are other key moderating factors involved in the expression of body dissatisfaction-linked attentional bias.

Digital safety plan effectiveness and use: Findings from a three-month longitudinal study.

Few studies have examined the effectiveness of self-guided smartphone apps for suicide safety planning, despite their increasing use. Participants (n = 610) were self-selected users of the Beyond Now suicide prevention safety planning app with a history of suicidal thoughts and behaviours. Surveys were completed (baseline, one and three months), safety plan content and app usage data was shared. Repeated-measures ANOVAs examined changes in suicidal ideation and suicide-related coping over three months. Multiple regression models were used to predict suicidal ideation and suicide-related coping at one- and three-month follow-ups with plan-related variables: perceived usefulness, personalised content, app use time and co-authoring of the plan with a third party. Significant reductions in suicidal ideation and increases in suicide-related coping were found over three months. Higher suicide-related coping at three months predicted lower suicidal ideation. Higher perceived usefulness and personalised content at three months were associated with higher suicide-related coping, but not suicidal ideation. App use time and co-authoring were not significantly related to suicidal ideation or suicide-related coping. Practitioners should empower clients to create safety plans with personalised (not generic) strategies that a client perceives to be useful. Such plans may strengthen beliefs about coping with suicidal ideation, which in turn reduces suicidal ideation over time.

Current evidence on the efficacy of mental health smartphone apps for symptoms of depression and anxiety. A meta-analysis of 176 randomized controlled trials.

The mental health care available for depression and anxiety has recently undergone a major technological revolution, with growing interest towards the potential of smartphone apps as a scalable tool to treat these conditions. Since the last comprehensive meta-analysis in 2019 established positive yet variable effects of apps on depressive and anxiety symptoms, more than 100 new randomized controlled trials (RCTs) have been carried out. We conducted an updated meta-analysis with the objectives of providing more precise estimates of effects, quantifying generalizability from this evidence base, and understanding whether major app and trial characteristics moderate effect sizes. We included 176 RCTs that aimed to treat depressive or anxiety symptoms. Apps had overall significant although small effects on symptoms of depression (N=33,567, g=0.28, p<0.001; number needed to treat, NNT=11.5) and generalized anxiety (N=22,394, g=0.26, p<0.001, NNT=12.4) as compared to control groups. These effects were robust at different follow-ups and after removing small sample and higher risk of bias trials. There was less variability in outcome scores at post-test in app compared to control conditions (ratio of variance, RoV=-0.14, 95% CI: -0.24 to -0.05 for depressive symptoms; RoV=-0.21, 95% CI: -0.31 to -0.12 for generalized anxiety symptoms). Effect sizes for depression were significantly larger when apps incorporated cognitive behavioral therapy (CBT) features or included chatbot technology. Effect sizes for anxiety were significantly larger when trials had generalized anxiety as a primary target and administered a CBT app or an app with mood monitoring features. We found evidence of moderate effects of apps on social anxiety (g=0.52) and obsessive-compulsive (g=0.51) symptoms, a small effect on post-traumatic stress symptoms (g=0.12), a large effect on acrophobia symptoms (g=0.90), and a non-significant negative effect on panic symptoms (g=-0.12), although these results should be considered with caution, because most trials had high risk of bias and were based on small sample sizes. We conclude that apps have overall small but significant effects on symptoms of depression and generalized anxiety, and that specific features of apps - such as CBT or mood monitoring features and chatbot technology - are associated with larger effect sizes.

The efficacy of mindfulness apps on symptoms of depression and anxiety: An updated meta-analysis of randomized controlled trials.

Mindfulness apps have become popular tools for addressing symptoms of depression and anxiety. Since the publication of earlier meta-analyses evaluating the efficacy of mindfulness apps for depression and anxiety symptoms, over 20 randomized controlled trials (RCTs) have been conducted. There is a need for an updated meta-analysis that quantifies the effects of mindfulness apps on these symptoms and tests for potential moderators.. Random effects meta-analyses were conducted on 45 RCTs. Small, significant effect sizes were found for symptoms of depression (Ncomp = 46, N = 5852, g = 0.24, 95% CI = 0.17, 0.31, NNT = 13.57) and anxiety (Ncomp = 48, N = 6082, g = 0.28, 95% CI = 0.21, 0.35, NNT = 11.47) in favour of mindfulness apps over control groups. This effect was not explained by symptom deterioration in participants allocated to control groups. Effects remained stable when restricting analyses to lower risk of bias and larger sample trials. No significant moderators were observed, except trials that offered monetary compensation produced larger effects on depression. Non-significant effects were observed when comparing mindfulness apps to active therapeutic comparisons (g = -0.15 depression, g = 0.10 anxiety), though the number of studies was low. Growing evidence indicates that mindfulness apps can acutely reduce symptoms of depression and anxiety, although higher quality studies with longer follow-ups are needed.