Clinical psychology is stalled. Treatment effect sizes have plateaued, syndromal diagnosis has not yielded actionable mechanisms, reliance on WEIRD-centric research limits cultural relevance, and rising mental-health needs continue to outstrip available care. New therapeutic brands keep appearing, yet few new principles or processes emerge, and practitioners still lack scientific guidance for fitting interventions to particular people's lives. These problems have many causes. One is deep and correctable: the ergodic error. Psychologists routinely apply average findings from ensemble-level statistics to particular people without verifying the assumptions that make such applications valid. This error is not incidental to clinical science's history. Population-ranking methods were originally developed for eugenic aims; clinical science retained their logic while abandoning their aims, yielding an analytic system poorly suited to the applied task: predicting and influencing what particular people do, in a particular context, over time. To move beyond this impasse, we propose idionomic analysis, which begins with idiographic modeling of change processes in particular people (e.g., individuals, couples, families), then derives functional groupings and nomothetic principles, retaining only those that deepen idiographic understanding. We discuss supporting algorithms: i-ARIMAX, iBoruta/tsBoruta, GIMME/S-GIMME, GSOM, Multilevel-VAR, idionomic random-effects meta-analysis, and PECAN/PLAN. Matching analytic methods to the demands of intervention is not a technical adjustment. It changes what applied life science can coherently claim, what will replicate, and whether personalized care is built from evidence about the clients being treated, or from averages that may describe no one.
BACKGROUND:Loneliness, including its associations with mental health, is recognised as a major global public health concern. While much research has focused on chronic loneliness, state loneliness - experienced in moment-to-moment contexts - remains underexplored. This gap is important, as daily experiences may provide critical opportunities for intervention. Intensive data collection approaches such as Ecological Momentary Assessment (EMA), Experience Sampling Method (ESM) and Daily Diary are well-suited for moment-to-moment capture and a review of their use for illuminating loneliness would be valuable for characterizing the state of the art and identifying gaps. This review thus synthesised findings from the intensive data collection approach to explore factors that may influence state loneliness and its consequences for mental health/well-being across all ages, providing valuable insights for targeted interventions. METHOD:This review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Four databases (PsycINFO, PubMed, Web of Science, and EMBASE) were searched from inception to 25th May 2026. Abstracts and full texts were screened, and the quality of the included studies was assessed. Data extraction was conducted independently by two reviewers. RESULTS:One hundred and seventeen studies were included in this review, addressing measurement practices and quality (RQ1-2), predictors and correlates of state loneliness (RQ3), and mental health and wellbeing outcomes (RQ4). State loneliness was predominantly assessed using single items with varied response formats; most items met expert-based formulation criteria, though empirical psychometric evidence was rarely reported. Associations were observed between state loneliness and mental health outcomes (e.g., internalising, suicidality) and social interaction, with several studies reporting effects in both directions, though the nature of these associations varied with study design and analytic approach. Other factors, including physical health, age, and gender, were also linked to state loneliness. DISCUSSION:Taken together, the review provides an improved understanding of the factors that may influence loneliness and its consequences for mental health/well-being. The results of the review could help to inform targeted prevention and intervention strategies for all age ranges, facilitating the mitigation of loneliness.
Adolescence or youth, spanning ages 12-24, represents peak vulnerability for mental health problems but also offers cognitive plasticity and thus optimal opportunity for interventions. Meanwhile, the science of mental imagery is fuelling innovations in mental health, but mostly in adults. In this review, we aim to spotlight mental imagery in youth mental health, highlighting its potential for driving theoretical and therapeutic innovations. We synthesise the current evidence for imagery's role in understanding and addressing psychopathology, focussing on emerging youth data. Central to this review, we propose a novel framework in which mental imagery acts as a "developmentally sensitive amplifier" during adolescence, intensifying key cognitive-emotional processes that are salient at this developmental stage - particularly threat, reward, and self-processing - and thereby increasing their influence on the development of psychopathology. Therapeutic implications and translational considerations are discussed within a developmental and delivery context in youth. By integrating cognitive, clinical, and developmental sciences, imagery-based approaches could yield powerful interventions to tackle the global challenge of youth mental health.
Despite important research efforts devoted to testing the effectiveness of psychological interventions for the treatment of common mental disorders in low- and middle- income countries (LMICs), a gap remains in the field of prevention. We searched multiple databases up to May 7, 2026 for randomized controlled trials (RCTs) testing task-sharing psychological interventions for preventing common mental disorders in adults living in LMICs. Prevention interventions were classified into indicated, selective and universal. Primary outcomes were the diagnosis and symptom decrease of depression, PTSD, and anxiety at post-intervention. We estimated risk ratios (RRs) and standardized mean differences (SMDs) using random effects pairways and network meta-analyses (NMA). Protocol registration: CRD42023402399. We included 81 RCTs with 10,747 participants. 41 RCTs tested indicated, 34 selective and 7 universal prevention interventions. For preventing depression, wellbeing promotion, parental psychoeducation, yoga/mindfulness, and multi-component interventions were more effective than enhanced treatment as usual (ETAU/TAU) (RR 0.25 to 0.66). In head-to-head comparisons, wellbeing promotion and psychoeducation ranked highest (Surface Under the Cumulative Ranking, SUCRA>90%). In reducing depressive symptoms, parental psychoeducation, social support, wellbeing promotion, yoga-mindfulness, cognitive behavioral therapy, multicomponent interventions were more effective than ETAU/TAU (SMDs -0.94 to -0.36). For PTSD prevention, yoga-mindfulness, parental psychoeducation, CBT, and multicomponent interventions reduced symptoms. For anxiety diagnosis and symptoms, wellbeing promotion, social support, yoga-mindfulness, multicomponent interventions, and active waiting list were the most effective interventions. Extensive evidence supports the effectiveness of task-sharing psychosocial interventions in preventing mental disorders in LMICs, with stronger evidence for indicated and selective prevention.
The comparative efficacy of acceptance and commitment therapy (ACT) relative to other bona fide psychotherapies has been obscured by methodological limitations and variability in how ACT and active comparators are operationalized. We therefore conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing full-model ACT (therapist-delivered, multi-session interventions targeting the core ACT processes) to bona fide psychotherapies. We identified 34 RCTs meeting our inclusion criteria. In line with prior critiques of the ACT literature, we identified several common methodological shortcomings, such as lack of preregistration of primary outcomes and hypotheses, inadequate statistical power for detecting differential effects, limited use of intent-to-treat analyses, and interpretive overreach. Random-effects three-level meta-analyses indicated that full-model ACT was not superior to bona fide psychotherapies on mental and behavioral health outcomes (g = -0.01, p = .86). Secondary, hypothesis-generating post hoc analyses examined clinical significance, ACT-targeted processes, and an exploratory TOST comparison against a prespecified equivalence region (g = ±0.20). Current RCT evidence does not justify recommending full-model ACT over other established treatments. Further progress will require more rigorous comparative trials and idiographic designs that better align with the ACT model.
INTRODUCTION:No recent comprehensive meta-analysis has integrated the results of randomized controlled trials of Behavioral activation (BA), one of the most important treatments of depression. METHODS:We used the data from our meta-analytic research domain of randomized controlled trials on the treatment of depression and selected all trials on BA in all age and target groups, settings and comparators. RESULTS:We included 105 trials (13,933 patients), including 40 with low risk of bias. The standardized mean difference (SMD) of BA for adult outpatients compared with control conditions was 0.67 (95% confidence interval [CI]: 0.54 to 0.80; k = 61) with high heterogeneity (I2 = 71%; 95% CI: 63% to 78%) and a broad 95% prediction interval (PI; -0.11 to 1.46). This remained significant in most sensitivity analyses, and at 12 months after randomization. We found no significant difference between BA and other therapies (k = 27; SMD = 0.04; 95% CI: -0.10 to 0.18). Self-guided BA was also effective (k = 15; SMD = 0.36; 95% CI: 0.20 to 0.51), as was BA in institutional settings (k = 10; SMD = 0.36; 95% CI: 0.17 to 0.55). Too few trials were available to estimate the effects of BA in children and adolescents (k = 4) and when compared to pharmacotherapy in adults (k = 4). CONCLUSION:BA is an efficacious treatment of depression in adults and its effect is significant up to 12 months after randomization. BA has smaller but significant effects in a self-guided format and in institutional settings.
BACKGROUND:Clinical psychological science has shown limited progress in improving treatment efficacy, refining intervention models, and identifying processes of change, that are traditionally associated with common factors (such as therapeutic alliance and empathy). OBJECTIVE:To examine research trends on this topic, we systematically surveyed the literature for studies that examine processes of change in the context of psychological interventions. METHODS:A total of 778 studies reported on 684 processes of therapeutic change since 2007. Using an iterative, AI-assisted human-in-the-loop clustering procedure, these processes were subsequently organized into 32 process clusters using OpenAI's GPT-5 nano model. RESULTS:The largest process cluster identified concerned common factors (i.e., therapeutic alliance and collaborative processes, and interpersonal functioning), accounting for 20.6% of all investigated processes of change. The remaining processes were primarily associated with specific factors related to cognitive behavioral therapy, such as cognitive appraisal and belief change processes. The research focus and number of studies on therapeutic processes have not changed substantially over the years. CONCLUSION:Despite urgent calls to improve our understanding of therapeutic processes, the focus and volume of research have remained unchanged, with the primary focus remaining on common factor processes.
While humor is increasingly recognized as a valuable adjunct to traditional, symptom-focused treatments for depression, there remains a lack of integrated clinical guidance for its use. This narrative review synthesizes findings from clinical psychology and humor research to provide a comprehensive analysis of the therapeutic potential of and contraindications to humor interventions in depressed populations. The review examines both the benefits-including emotional gain, responsiveness to humorous material, and the effects of humor-based interventions-and the risks-such as impaired humor skills and possible adverse effects-before integrating the two to offer recommendations for identifying good candidates for humor interventions and for tailoring the content to the profiles of people with depression. Particular consideration is given to the different stages of depressive disorders, the heterogeneous nature of humor, its role as an emotion regulation strategy, and its integration into broader therapeutic frameworks. The review concludes by emphasizing the need for specialized education for practitioners and considering the potential of digital technologies and priorities for future research.
Intolerance of uncertainty (IU) has been widely conceptualized as a transdiagnostic vulnerability factor for worry and anxiety; however, the extent to which the associations among IU, worry, and anxiety outcomes vary across clinical phenotypes and broader contextual and methodological conditions has not yet been fully integrated within a unified framework. This pre-registered meta-analysis tested a structural model of IU → worry → anxiety while also examining the moderating role of key clinical, developmental, and measurement-related factors, synthesizing 738 effect sizes from 115 studies/dissertations comprising 138 independent samples (N = 28,693). Beyond confirming robust associations between IU-worry (r = .59), the analysis reveals a systematic hierarchical pattern in IU-anxiety relationships across disorders. IU showed strongest associations with GAD (r = .54) and non-specific anxiety (r = .48), followed by PTSD (r = .46), social anxiety disorder (r = .45) and OCD (r = .41), and comparatively weaker links with panic disorder (r = .27). This gradient provides the first quantitative evidence that the transdiagnostic relevance of IU varies in a theoretically coherent hierarchy across anxiety outcomes. Worry demonstrated even stronger associations, particularly with GAD (r = .67), and remained significantly linked to anxiety after accounting for IU. Meta-analytic structural equation modeling confirmed worry as a partial mediator of the IU-anxiety relationship, with the largest indirect effects for GAD (r = .32), followed by non-specific anxiety (r = .22), social anxiety disorder (r = .17), panic disorder (r = .15), PTSD (r = .14), and the smallest effect observed for OCD (r = .13). Moderator analyses were significant and revealed stronger effects for IU-GAD, IU-non-specific anxiety, and worry-non-specific anxiety when assessed with overlapping self-report measures (p < .05), indicating greater construct proximity. In contrast, IU-OCD showed weaker effects under overlapping measurement conditions. IU-anxiety associations were weaker in the presence of depressive symptoms and varied across anxiety phenotypes. Overall, findings characterize IU as a distal factor and worry as a proximal cognitive process, refining transdiagnostic models through a hierarchical uncertainty-related architecture and complementary intervention targets.
Mindfulness, mindful eating and intuitive eating practices are associated with healthier eating and lower body weight. However, experimental research in this area has shown mixed effects on food intake and theoretical accounts are underdeveloped. This systematic review and meta-analysis aimed to examine the effect of mindfulness, mindful eating and intuitive eating interventions on food intake and appetite (hunger and fullness) in adults and children and compare effects across different subgroups to investigate potential mechanisms of action. Five electronic databases (PsycINFO, MEDLINE, EMBASE, Web of Science and Scopus) were searched for studies that experimentally manipulated mindfulness and/or mindful eating and/or intuitive eating, included a non-mindfulness control group and measured food intake (kcal or grams or percentage consumed or number of pieces consumed) and/or appetite (using visual analogue scales). Forty-one articles assessing mindfulness and mindful eating interventions were included (no relevant intuitive eating interventions were identified). Random-effects meta-analyses showed that mindfulness/mindful eating reduced food intake (n = 46 studies, SMD = -0.24, 95% CI [-0.35, -0.12], p < 0.001) but had no statistically significant effect on appetite (n = 11 studies). There were no significant subgroup differences observed between studies with different settings, interventions or food intake measures. However, effect sizes were substantially larger in laboratory-based studies. Overall, findings indicate that mindfulness and mindful eating reliably reduce food intake in controlled settings, but currently there is no evidence they influence appetite. The review underscores the need for higher quality and more ecologically valid studies using sensitive, real-world measures of appetite and food intake, and further work to clarify the mechanisms of action underpinning the effects of mindfulness and mindful eating.
In psychological therapy, clinical training and practice is usually based on one or several of the traditional theoretical treatment orientations' subvariants and varies considerably from country to country. However, no traditional clinical theory provides a fully defined and tested causal network between concepts of disorders and clinical interventions that includes tests of alternative explanations. Adhering to the traditional orientations also bears the risk of hindering innovation and the dynamic exchange of ideas. As a consequence, therapists decide which theory to follow based on their country's specific regulations and their personal taste. In this position paper, we recommend that the field moves toward evidence- and practice-based, personalized treatment planning and interventions that focus on patients' specific problem patterns and actual treatment progress, instead of prioritizing one theoretical framework. We present an open framework for evidence-based, transtheoretical, and transdiagnostic psychological therapy. This framework could stimulate progress in research as well as future developments in competence-based clinical training and practice.
The reciprocal relationships between bullying perpetration and victimization represent a critical yet understudied aspect of interpersonal aggression. This meta-analysis synthesized longitudinal evidence from 83 studies to systematically examine: (1) whether bullying perpetration predicted subsequent victimization, and (2) whether victimization conversely predicted future perpetration. We implemented a strategic search across five databases (Web of Science Core Collection, PsycINFO, MEDLINE, ProQuest, and China National Knowledge Infrastructure) to retrieve potentially eligible reports published from inception to 29 March 2026. The meta-analysis included 83 articles (88 samples, N = 124,075). Participants were 4.00-21.24 years old at T1 (M = 12.96, SD = 2.70). Employing robust random-effects modeling, this study found that bullying perpetration longitudinally and positively predicted bullying victimization (r = 0.252, 95% CI = [0.230, 0.273], p < .001), and bullying victimization also longitudinally and positively predicted bullying perpetration (r = 0.255, 95% CI = [0.235, 0.276], p < .001), indicating moderate bidirectional effects. Notably, these relationships were moderated by age, time lag, country of origin, types of bullying, measurement instruments, and the nature of items. Specifically, the predictive effect of bullying perpetration on victimization was stronger when the study was conducted in the U.S., when Wright and Li's Bullying Scale (2013) was used, and when multiple-item measures were employed. Conversely, the effect of bullying victimization on perpetration was stronger under the following conditions: older participants, shorter time lags, samples from the U.S. or Spain, cyberbullying settings, use of the Wright and Li's Bullying Scale (2013), and employment of multiple-item scales. The findings advance the theoretical understanding of bullying as a self-perpetuating cycle while highlighting the need for targeted interventions that address both perpetration and victimization.
Experimental psychopathology (EPP) historically relied on extensive experimenter training, but this has dwindled in recent years. Insufficient training may lead to increased 'experimenter noise' and 'protocol drift', potentially hindering the fidelity and replicability of EPP research. This may ultimately impact translation of findings from the laboratory to the clinic, decelerating the development of novel psychological interventions. In an effort to address this, we made a first attempt to develop experimenter training guidance for EPP researchers, using the example of the trauma film paradigm (TFP). In a pragmatic review of articles on methodological guidance for laboratory-based EPP paradigms, we identified only seven articles, just one of which provided an explicit framework for experimenter training. Incorporating insights from the reviewed articles, together with approaches employed in adjacent clinical trials, we suggest a possible framework for experimenter training in EPP. The framework includes overarching principles of experimenter training, steps in a training process, an approach to evaluating training outcomes, and offers examples from the TFP. Further work is needed, and future directions include incentivizing, improving, disseminating and experimentally testing guidance for experimenter training in EPP. Critically, as we have seen in previous decades, this may even ultimately aid the turbulent translational pipeline of new techniques from the laboratory to evidence-based psychological therapies grounded in scientific principles.
OBJECTIVE:For many, ill mental health and alcohol or other drug problems go hand in hand, resulting in complex presentations requiring specialised approaches. This review summarises recent evidence on the efficacy of family-inclusive approaches in the treatment of patients with a dual diagnosis. METHOD:A systematic search of five databases from January 2000 to February 2026 yielded 12,776 records, with 28 meeting inclusion criteria. RESULTS:Included studies reported on two distinct cohorts: adolescents, presenting with a mental health diagnosis and substance use, and adult clients, predominantly in hospital care due to a severe mental health condition paired with serious substance use of often more than one substance. In both cohorts, most studies found family-inclusive treatment approaches performed as well or better than treatment-as-usual for underlying conditions and for global and family functioning (adolescents, adults), family conflict, parental skills and family communication (adolescents). DISCUSSION:The intertwining of two serious health conditions is particularly challenging for practitioners, families and clients alike. Our findings show that family-inclusive interventions not only improve relational wellbeing of clients with their families but also have a positive impact on both mental health and substance use related conditions. By identifying effective ways of integrating families in treatment and highlighting gaps and further needs, these findings may assist the field to further prioritise family-inclusive approaches, and the added leverage they offer in the life of those facing complex health challenges. PROSPERO registration: CRD42023446988.
Children and adolescents with autism spectrum disorder (ASD) frequently experience emotion regulation (ER) difficulties, yet the comparative effectiveness of available interventions remains unclear. This network meta-analysis (NMA) aimed to rank non-pharmacological ER interventions for autistic children and adolescents and to examine moderators of treatment effects. Ten databases were searched from inception to March 2026. Randomized and controlled trials evaluating ER interventions in autistic youth (mean age < 18 years) were included. A frequentist NMA was conducted using random-effects models. Effect sizes were expressed as standardized mean differences (Hedges'g), with rankings estimated using surface under the cumulative ranking curve (SUCRA) values. Thirty-eight studies (1895 participants) were included; 32 contributed to the NMA. Technology-aided instruction and intervention (TAII) ranked first (SMD = 0.90, SUCRA = 79.4%), followed by drawing therapy (SMD = 0.88, SUCRA = 73.0%) and floortime (SMD = 0.81, SUCRA = 68.4%). Cognitive behavioral therapy showed moderate effects (SMD = 0.52, SUCRA = 43.7%). Subgroup analyses indicated that intervention rankings varied by duration, setting, informant, and age. This NMA establishes the evidence-based hierarchy of ER interventions for autistic youth. TAII and CBT are most effective overall, but effectiveness is context-dependent, supporting a personalized, stepped-care approach.
Depressive realism suggests that depressed individuals may make more accurate or realistic judgments than nondepressed counterparts. This meta-analytic study (130 articles, 151 samples, N = 33,043) synthesized findings on the relation between depressive mood and the accuracy of judgment, and investigated the conditions under which depressive realism or its opposite-depressive distortion-emerges. Overall, results indicated a weak but significant depressive distortion effect (Hedges's g = 0.09). Moderator analyses showed that the depressive realism was more likely when tasks involved control or contingency judgments, were analytically complex, and self-referent. By contrast, depressive distortion was more likely in severe clinical depression, with tasks that were non-self-referent, low in complexity, or involved ambiguous social information. Notably, distortion effects were more often observed in studies that did not acknowledge depressive realism. This review clarifies mixed findings on the depression-accuracy relation by identifying task-specific moderators, offering implications for theory and clinical practice.
Background Reducing duration of untreated psychosis (DUP) is a priority for mental health services worldwide. Delayed help-seeking leads to prolonged DUP which is associated with poorer healthcare outcomes. Methods Most of the research in this area is qualitative. We conducted an electronic search of relevant databases (MEDLINE, APA PsycArticles, APA PsycINFO, and CINAHL) using terms for early psychosis, help-seeking and qualitative analyses. Following best practice guidelines for reviews of qualitative research, we extracted and thematically synthesised data from all included articles. Results The search yielded thirty papers. Synthesis of the results generated five domains of facilitators and barriers to help-seeking: (a) knowledge of psychosis and services; (b) role of family and friends; (c) stigma of psychosis and help-seeking; (d) relationship with clinicians; and (e) experience of services. Conclusion This is the first systematic review of the qualitative research examining first person accounts of help-seeking in high risk and first episode psychosis. We integrate these findings with an established theory of help-seeking to generate a novel model of help-seeking in early psychosis that can now be used to predict engagement and disengagement from services, and shape routine clinical practice to reduce DUP.
Chronotype, a person's natural timing for sleep and daily activity, has been increasingly linked to eating patterns and obesity risk. However, evidence regarding its association with disordered eating indicators remains inconsistent. We systematically reviewed and meta-analyzed the association between chronotype and disordered eating indicators in the general population. Fifty-one observational studies were included, with a mean age and BMI of participants ranging from 13.3 to 52.6 years and 19.83-40.60 kg/m2. Later chronotype was associated with higher scores in binge-eating (r: 0.39; 95% CI, 0.35, 0.43; p < 0.001; I2 = 94.38%, p < 0.001), night-eating (r: 0.21; 95% CI, 0.15, 0.27; p < 0.001; I2 = 75.61%, p < 0.001), food addiction (r: 0.17; 95% CI, 0.11, 0.22; p < 0.001; I2 = 78.99%, p < 0.001), emotional eating (r: 0.06; 95% CI, 0.03, 0.09; p < 0.001; I2 = 41.59%, p = 0.060), uncontrolled eating (r: 0.13; 95% CI, 0.08, 0.18; p < 0.001; I2 = 72.84%, p < 0.001), and food craving (r: 0.09; 95% CI, 0.06, 0.12; p < 0.001; I2 = 69.97%, p = 0.010). Conversely, later chronotype was associated with lower restrained eating (r: -0.11; 95% CI, -0.15, -0.07; p < 0.001; I2 = 0.00%, p = 0.440). Later chronotype is consistently linked to a spectrum of disordered eating indicators among general populations. These outcomes highlight an association between chronotype and disordered eating indicators; however, more longitudinal and randomized controlled trials are needed to establish causality and underlying mechanisms.
