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Infective endocarditis remains a serious condition. Patients with CHD are particularly susceptible due to structural abnormalities and repeated interventions. However, comparative data on infective endocarditis outcomes in patients with and without CHD stratified by age group remain limited.
Methods:
We searched PubMed, Embase, and Cochrane for cohort studies comparing infective endocarditis outcomes in CHD versus non-CHD. Risk ratios with 95% confidence intervals were pooled using random-effects models.
Results:
We included six observational cohort studies encompassing 180,194 patients, of whom 176,882 were adults and 3312 were children. Overall, 65% of the population were male. Patients with CHD tended to be younger and carried a lower comorbidity burden. CHD was associated with lower in-hospital mortality risk in adults (RR 0.42; 95% CI 0.34–0.53; p < 0.01), whereas children with CHD demonstrated higher risk (RR 1.59; 95% CI 1.08 to 2.32; p = 0.02). Streptococcus infective endocarditis was more common in adults with CHD (RR 1.28; 95% CI 1.09 to 1.50; p < 0.01), while Staphylococcus aureus infective endocarditis was less common in both adults (RR 0.71; 95% CI 0.58 to 0.88; p < 0.01) and paediatric (RR 0.73; 95% CI 0.64 to 0.84; p < 0.01) CHD patients.
Conclusion:
In this meta-analysis, mortality patterns in CHD varied by age, with lower mortality in adults and higher mortality in children. Streptococcus infective endocarditis was more common in adults with CHD, whereas Staphylococcus aureus was less frequent across CHD age groups. These results highlight the need for age-specific and individualised endocarditis management in CHD.
This systematic review and meta-analysis aimed to quantify the magnitude of placebo and nocebo effects in pharmacological trials for OCRDs and identify clinical and methodological moderators influencing these effects.
Methods:
A comprehensive literature search was conducted across multiple databases and clinical trial registries up to May 2025. Randomized, placebo-controlled trials involving pharmacological interventions for OCRDs were included. The primary outcomes were placebo effect size and placebo response rate; secondary outcomes included nocebo response rate and side effect profile. Data were extracted independently and meta-analysed using random-effects models. Meta-regression was performed to assess moderators of placebo response.
Results:
Fifteen eligible trials (N = 640; placebo N = 341) were included. The pooled placebo effect size was moderate (SMC = -0.63; 95% CI -0.77 to -0.48), with low heterogeneity (I2 = 4.73%). The placebo response rate was 21%, and the nocebo response rate was 18%. Despite testing a broad range of potential moderators, including clinical characteristics, methodological design, and medication class, no significant predictors of placebo effect size were identified. Side effects were reported in nearly one-third of placebo recipients, underscoring the relevance of nocebo effects.
Conclusions:
Placebo and nocebo responses are noteworthy in trials for OCRDs and may influence perceived treatment efficacy. Variability in placebo responses is not well explained by currently measurable moderators. Further research is needed to explore neurobiological, psychological, and methodological contributors to expectancy effects in OCRD pharmacotherapy trials.
To synthesize and quantify the association between household food insecurity (HFI) and various forms of malnutrition that includes stunting, wasting, underweight, overnutrition, and anaemia among Indonesian children under five years of age.
Design:
Systematic review and meta-analysis conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The study included literature search, screening, data extraction, quality assessment using Joanna Briggs Institute (JBI) tools, and meta-analysis using Review Manager 5.4.
Setting:
Studies conducted in Indonesia, covering urban, rural, and mixed settings across multiple provinces.
Participants:
Children under five years of age residing in Indonesia, from households assessed for food insecurity using validated tools.
Results:
A total of 32 studies met the inclusion criteria, of which 26 were eligible for meta-analysis. HFI was significantly associated with higher odds of stunting (case-control: OR = 4.66; 95% CI: 3.39–6.40; P < 0.001; cross-sectional: OR = 4.61; 95% CI: 4.17–5.11; P < 0.001;), wasting (OR = 1.92; 95% CI: 1.60–2.32; P < 0.001), underweight (OR = 5.26; 95% CI: 2.12–13.04; P < 0.001), and overnutrition (OR = 1.66; 95% CI: 1.49–1.85; P < 0.001). Children in food-secure households had significantly lower odds of anaemia (OR = 0.41; 95% CI: 0.30–0.58; P < 0.001).
Conclusions:
Household food insecurity is strongly associated with multiple forms of malnutrition among Indonesian children under five. These findings highlight the urgent need for integrated, nutrition-sensitive strategies that address food security to improve child health and reduce malnutrition in Indonesia.
Antipsychotics used to treat severe mental illness (SMI) markedly raise the risk of metabolic syndrome. Early weight gain predicts worse outcomes, making timely intervention vital, particularly within the first 6 months, when the most weight loss is achievable. This meta-analysis evaluated non-pharmacological weight/body mass index (BMI) management interventions during the first 6 months of their use in people receiving antipsychotics for SMI, to identify effective components with the aim of preventing long-term metabolic complications. Systematic searches of five databases (to October 2024) yielded 1483 studies; 8 (643 participants) met inclusion criteria. Interventions included exercise, nutrition, education, monitoring and psychological input, delivered individually or in groups.
Results
Meta-analysis showed significant weight (−1.93 kg) and BMI (−1.12 kg/m2) reductions. Group-based, multi-component programmes with psychological input were most effective.
Clinical implications
Group-based, multi-component interventions that include a psychological element produced the greatest reductions in weight and BMI. Future research should focus on refining and embedding psychologically informed, multi-component group programmes into routine psychiatric care to optimise long-term physical health outcomes.
The 2019 ICH E9(R1) addendum highlights the importance of estimands, including the specification of post-randomization events that may affect the interpretation of clinical trial outcomes (i.e., intercurrent events; ICEs) and strategies to handle these events. Compared to trial protocols, there is limited discussion of estimands in the context of evidence synthesis. We conducted a comprehensive review of the Cochrane Library for pairwise meta-analyses of immuno-, targeted, hormone, and other novel oncology therapies. Dates were restricted to 2021 and onwards to allow time for addendum adoption. Outcomes of interest were progression-free survival (PFS) and overall survival (OS). Information on treatment switching and analytic strategies to address treatment switching were extracted from each meta-analysis and the RCTs they included. Out of 162 oncology reviews published in the Cochrane Library since 2021, eight pairwise meta-analyses and 68 RCTs met selection criteria. Most RCTs were Phase 3 (68%; n = 46) and/or open-label (76%; n = 52). More than half of RCTs explicitly allowed switching (59%; n = 40), while more than one third (38%; n = 26) did not report on treatment switching. Among trials that allowed treatment switching, censoring mechanisms for treatment switching varied in analyses of PFS. No included RCTs censored OS at the time of treatment switching. Despite the high prevalence of treatment switching in included trials, none of the identified meta-analyses addressed treatment switching analytically. Poor reporting regarding treatment switching in the RCTs themselves hinders the utility of aggregate-level meta-analyses. To ensure accurate interpretation of meta-analytic results, improved reporting of ICEs and ICE handling strategies is needed.
Meta-analysis synthesizes evidence from multiple randomized clinical trials and informs evidence-based practices across various medical domains. Recently, causally interpretable meta-analysis has been proposed and applied to treatment evaluations for target populations, requiring individual participant data (IPD). Standard meta-analysis assumes transportability or exchangeability of a (conditional) relative effect (such as relative risk or odds ratio), which may be violated when the relative effects are correlated with the baseline risks across clinical trials. In addition, the weighted average of some study-specific effect measures such as the (log) odds ratios or the (log) hazard ratios is non-collapsible and does not correspond to any target population. Furthermore, when the randomization ratios between treated versus untreated arms vary across trials, confounding bias may occur. To address these challenges, we propose a causal meta-analysis (CMA) framework using only aggregated data, enabling causally interpretable and accurate estimation for different target populations. The CMA adjusts its weights for treatment effect across various target populations, including the average treatment effect (ATE), the ATE on the treated (ATT) population, the ATE on the control (ATC) population, and the ATE in the overlap (ATO) population. Mathematically, we discover the connection between traditional meta-analysis estimators and CMAs. For example, the Mantel–Haenszel weighted meta-analysis is equivalent to the CMA with ATO.
While it is known that speakers tend to use more reduced forms for more predictable words or phrases, it is unclear whether the same happens at the referential level: the influence of referent predictability on pronoun production remains a contentious issue, with divergent findings reported in the literature. To address this inconsistency, we carried out a Bayesian meta-analysis of the current literature on the relationship between referent predictability and pronoun production. Our meta-analysis covers twenty primary peer-reviewed studies, encompassing twenty-six experiments across eight languages. We find stronger evidence for a small positive effect of referent predictability on pronoun usage, as opposed to the alternative hypothesis of no effect or a negative effect. As the first comprehensive synthesis of available evidence on this topic, our study offers insights into pronoun production and identifies promising avenues for future research: focus on typologically diverse languages, on conditions where a variety of referring expressions are expected or where the effect of predictability is more likely to appear, and others. Finally, we also advocate for the use of meta-analysis as a tool for theoretical linguistics.
Acupuncture is a clinically recognized treatment for major depressive disorder (MDD), but the associations of efficacy with dosage, treatment course, frequency, acupuncture modality, needle retention time, and manipulation remain unclear. This study evaluated the efficacy and safety of acupuncture for MDD and explored potential moderating factors.
Methods
Randomized controlled trials of acupuncture for MDD were searched in CNKI, VIP Database, Wanfang Data, SinoMed, PubMed, Embase, Web of Science, and the Cochrane Library from inception to May 2025. Risk of bias was assessed using RoB 2, and certainty of evidence using GRADE. Data were analyzed in Stata 18.0.
Results
36 trials involving 3843 participants were included. Compared with sham/placebo acupuncture, acupuncture showed greater antidepressant effects (SMD −1.12, 95% CI −1.57 to −0.67, P < 0.01). Very low-quality evidence suggested similar efficacy between acupuncture and antidepressants. Electroacupuncture was superior to manual acupuncture (SMD −0.24, 95% CI −0.42 to −0.07, P < 0.01). High- and moderate-dose acupuncture were more effective than low-dose regimens, and meta-regression suggested a linear dose-response relationship, with 30 sessions as the optimal dosage. Better outcomes were associated with treatment course >6 wk, 3 times weekly, needle retention time of 20–30 minutes, and electroacupuncture. No significant difference was found between needle manipulation and non-manipulation.
Conclusions
Acupuncture significantly alleviates depressive symptoms in MDD. Efficacy appears to be influenced by dosage, acupuncture modality, treatment course, frequency, and needle retention time, with 30 sessions, treatment course > 6 wk, 3 sessions weekly, 20–30 minutes retention, and electroacupuncture showing the most favorable outcomes.
To compare the clinical efficacy and prognosis of Ozaki procedure and Ross procedure in the treatment of paediatric aortic valve disease.
Methods:
According to the predetermined inclusion and exclusion criteria, relevant clinical studies were comprehensively searched in three databases, and relevant data were extracted for analysis and comparison.
Results:
This meta-analysis included four retrospective cohort studies with a total of 243 patients (117 undergoing Ozaki procedure and 126 undergoing Ross procedure). There were no significant difference in the in-hospital all-cause mortality [odds ratio = 1.38; 95% confidence interval: 0.38, 5.07, p = 0.63] and all-cause mortality during the follow-up period [odds ratio = 1.85; 95% confidence interval: 0.54, 6.32, p = 0.32] between Ozaki procedure and Ross procedure. The reoperation on the aortic valve [odds ratio = 10.48; 95% confidence interval: 2.22, 49.40, p = 0.003] was higher in the Ozaki procedure than in the Ross procedure. There were no patients who underwent pulmonary valve reoperation after Ozaki procedure [odds ratio = 0.21; 95% confidence interval: 0.03, 1.23, p = 0.08]. The cumulative reoperation rate after Ozaki procedure [odds ratio = 2.29; 95% confidence interval: 0.93, 5.66, p = 0.07] was higher than that of Ross procedure, but the difference was not statistically significant. The cardiopulmonary bypass time after Ozaki procedure [odds ratio = −32.09; 95% confidence interval:−45.05, −19.14, p < 0.00001] was shorter than that of Ross procedure. The incidence of postoperative complications [odds ratio = 0.24; 95% confidence interval: 0.04, 1.62, p = 0.14], aortic cross-clamping time [odds ratio = −20.39; 95% confidence interval: −43.68, 2.90, p = 0.09], ventilator assistance time [odds ratio = 1.71; 95% confidence interval: −42.70, 46.13, p = 0.94], and ICU time [odds ratio = −0.38; 95% confidence interval: −0.93, 0.16, p = 0.17] in Ozaki procedure was not statistically significant compared to Ross procedure.
Conclusions:
In the treatment of children with aortic valve disease, there is no statistically significant difference between the Ozaki procedure and the Ross procedure in terms of freedom from reoperation and all-cause mortality.
This chapter focuses on the foundations of study design and statistical analysis in psychological research. It explores strategies for ensuring internal validity, such as randomization, control groups, and large sample sizes. Additionally, it addresses the complexity of human behavior by exploring multivariate experiments and the use of artificial intelligence and machine learning in neuroscience. The chapter also discusses the replication crisis and the emergence of open science practices, encouraging students to think critically about isolated scientific findings and offering tools for identifying credible research. Lastly, it critiques null hypothesis significance testing and p-values while providing an overview of key statistical topics like correlation coefficients, standardized mean differences, and regression.
Science is invariably based on some sort of data collection and further treatment of the data gathered. Data can come from pure observations, from structured observations (‘natural experiments’) or from experiments. The central importance of models in science is mentioned. It is discussed how the choice of statistics reflects the philosophy of science adopted by the scientist. Different research programmes use different statistics, in particular, depending on when and how they deal with variation. The relationship between falsificationism and the rejection of null hypotheses as a workaround for the Duhem-Quine thesis is discussed, as well as the role of significance thresholds and their associated problems. It is argued that predicted results are more reliable than chance findings. The pros and cons of having alternative hypotheses are discussed, and a short introduction to Bayesian statistics as an alternative to frequentist approaches is given. Systematic reviews and metaanalyses of data from several studies are introduced, and an example is given on how different types of evidence from many studies are combined to form the current consensus of rational opinion regarding a particular hypothesis.
Quality of life (QoL) is an important clinical outcome in mental health. However, evidence on its progression and predictors in individuals at clinical high risk for psychosis (CHR-P) remains limited. This meta-analysis examined correlates, impact, and longitudinal changes in QoL among CHR-P individuals.
Methods
Following PRISMA guidelines (PROSPERO: CRD42024560092), we systematically searched multiple databases from inception to 27 May 2025. Eligible studies included CHR-P participants assessed with validated QoL instruments. Data extraction was performed independently, and meta-analyses, meta-regressions, heterogeneity, and publication bias analyses were conducted. Risk of bias was evaluated using a modified Newcastle–Ottawa Scale (NOS).
Results
Thirty-one studies were included (2,288 CHR-P individuals; mean age = 21.47 years; 48.9% female). Compared with healthy controls (HC), CHR-P participants showed significantly poorer QoL (Hedges’ g = 1.39, 95% CI = 0.97–1.83). Longitudinal analyses indicated QoL improvements after 1 year (Hedges’ g = 1.40, 95% CI = 0.74–2.07) and at 2–3 years follow-up (Hedges’ g = 3.24, 95% CI = 0.73–5.75). Substantial heterogeneity was observed across analyses. Meta-regressions showed no significant influence of age, sex, functioning, symptom severity, or study quality. Study quality scores ranged from 1 to 8 (median = 6, mean = 5.8, SD = 1.13).
Conclusions
Individuals at CHR-P present markedly poorer QoL compared with healthy controls. Longitudinal data suggest possible improvements over time; however, heterogeneity and limited long-term evidence warrant cautious interpretation. Further longitudinal studies are needed to better characterize QoL trajectories and identify subgroups requiring sustained intervention.
Psychedelic-assisted psychotherapy has shown potential for psychiatric disorders. However, the magnitude of symptom change in control groups remains poorly understood. We aim to evaluate within-group effects in control groups and compare them to treatment groups in psychedelic trials.
Methods
A systematic search was conducted up to 1 July 2025. The study protocol was preregistered in PROSPERO (CRD420251111853).
Results
Fourteen randomized controlled trials (n = 643) were included. Direct between-arm meta-analyses showed greater symptom reductions in treatment compared with control across outcomes, including depressive symptoms (number of study arms [k] = 13; SMD = −0.82; 95% CI = −1.17, −0.47; I2 = 60.1%), posttraumatic stress disorder (PTSD) symptoms (k = 10; SMD = −0.89; 95% CI = −1.14, −0.65; I2 = 0%), and anxiety symptoms (k = 5; SMD = −0.66; 95% CI = −0.94, −0.38; I2 = 0%). Subgroup analyses showed limited evidence that effects differed by placebo type for depressive or PTSD symptoms. Descriptive within-group analyses indicated symptom reductions from baseline in both control and treatment groups, with larger within-group improvements observed in treatment groups across outcomes; notably, larger within-group reductions in PTSD symptoms were observed in inactive placebo groups. Sensitivity analyses showed consistent results.
Conclusions
Control groups in psychedelic trials demonstrated substantial symptom improvement, which may reflect non-specific trial factors (including expectancy and concurrent psychotherapy). These findings emphasize the importance of robust control conditions in psychedelic research and the need for nuanced interpretation of treatment effects.
This meta-analysis investigates the contributions of viewing audiovisual input on second language (L2) learning. We calculated 75 effect sizes from 56 experiments (n = 1954) and assessed the effects of audiovisual input on language learning using a within-group (pre-post) meta-analytic approach. Fifteen moderator variables were included in the analysis. Results showed that a) there was a small effect of audiovisual input on L2 learning (g = .89); b) no differences were found between the effects of viewing audiovisual input on different areas of L2 learning (vocabulary, grammar, pronunciation, speaking, listening proficiency); and c) video category had a significant impact on L2 learning with entertainment-focused videos (e.g., TV series, movies, and mixed videos) yielding lower effects than educational videos (e.g., TED Talks, documentaries, and language-focused).
1. Meta-analyses are a reliable method for a quantitative research synthesis. They are, however, prone to specific biases that can be introduced in the process. Such a bias could exist if primary literature produces similar results if coming from the same authors. Authorship network bias is the non-independence of effect sizes introduced by the overlap of authors of primary studies. If not accounted for, it can severely impact the quality of meta-analysis and the conclusions drawn from it.
2. To account for such non-independence, multilevel models with author clusters as an additional hierarchy level were recently suggested. We propose a new method for the detection of non-independent effect sizes based on authorship networks and for their correction.
3. An analysis of simulated data demonstrates the effectiveness of the here-suggested new method. We further applied our new method to nine exemplary meta-analyses.
4. Our new method for detection and effective correction can be easily integrated in existing meta-analysis workflows, using the functionality already offered by R’s metafor package.
5. Our goal is to enhance the reliability of meta-analyses by highlighting potential authorship network bias and offering a method to address this often-overlooked bias.
To compare the diagnostic accuracy of nasal endoscopy, computed tomography and magnetic resonance imaging for chronic rhinosinusitis and chronic rhinosinusitis with nasal polyps.
Methods
PubMed, Embase, Web of Science, Scopus and the Cochrane Library were searched from 1990 to August 2025. Studies reporting 2 × 2 diagnostic data for diagnostic nasal endoscopy, computed tomography or magnetic resonance imaging were pooled using random-effects models to estimate sensitivity, specificity and summary receiver-operating characteristic measures.
Results
Nine diagnostic datasets were included. Diagnostic nasal endoscopy showed high sensitivity (0.87) but moderate specificity (0.63) versus computed tomography. Computed tomography demonstrated good sensitivity (0.90) but limited specificity (0.50) versus histopathology. Magnetic resonance imaging provided moderate sensitivity (0.71) and high specificity (0.88) versus computed tomography. Substantial heterogeneity existed across modalities and reference standards.
Conclusion
Diagnostic nasal endoscopy is highly sensitive but moderately specific. Computed tomography is sensitive but limited by false positives. Magnetic resonance imaging appears more specific, although evidence remains scarce. Further paired imaging–histopathology studies are required.
'Transfiction' refers to the phenomenon of language mediators portrayed as characters in literature. Research investigating this phenomenon has developed through a long series of case studies. While providing in-depth analyses of different instances of transfiction, case studies have produced findings that are anchored to specific texts, consequently precluding theoretical observations at a higher level of abstraction. Thus, this Element constructs a concentrated profile of transfiction. It asks about the state of the art of this research area and its potential to inform other subfields of translation studies. By adopting a meta-analytical research style, the Element retraces the development of transfiction studies, identifying patterns and lacunae. It then goes on to thread transfiction together with previously disconnected research strands, such as translator studies, suggesting new research questions and methodologies. Ultimately, Charting Transfiction provides a reference point for future research in this area, as well as other subfields of translation studies.
The co-occurrence of psychotic disorders and borderline personality disorder (BPD) complicates clinical management, with overlapping symptoms exacerbating morbidity and impairing therapeutic outcomes. This systematic review and meta-analysis aimed to estimate the prevalence of psychotic disorders and BPD co-occurrence, including with first-episode psychosis (FEP) and to describe associated sociodemographic and clinical characteristics.
Methods
Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, four databases were systematically searched from inception to June 2025. Eighteen studies met the inclusion criteria. Data extraction and quality appraisal (Effective Public Health Practice Project tool) were conducted independently by two reviewers. Random-effects meta-analyses estimated pooled prevalence rates.
Results
The pooled prevalence of BPD in people with psychotic disorders was 22.7% (95% CI: 14.2–34.3%), while 14.3% (95% CI: 5.5–32.1%) of individuals with BPD had a comorbid psychotic disorder. In FEP samples, 40.0% (95% CI: 21.9–61.3%) met the criteria for BPD. People with both conditions, often young women, showed greater emotional dysregulation, suicidality, psychotic symptoms, and social dysfunction. Trauma, dissociation and substance use emerged as frequent vulnerability factors. However, most studies were cross-sectional, with small samples and high heterogeneity (I2 > 80%), limiting generalizability.
Conclusion
This co-occurrence constitutes a distinct clinical subgroup with complex needs. Categorical diagnostic approaches may fail to capture the dimensional nature of overlapping affective and psychotic symptoms. Integrative and personalized care pathways, especially in early intervention settings, are warranted. This review was registered in PROSPERO (CRD42024577525).
This systematic review and meta-analyses provide the first synthesis of the literature on trait mindfulness and psychotic-like experiences (PLEs). Theoretical models suggest a protective function of mindfulness and it is important to understand any potential role of mindfulness in the prevention and treatment of PLEs. We examined the following: (1) What is the relationship between trait mindfulness and PLEs in nonclinical populations?; and (2) What is the effect of mindfulness-based interventions (MBIs) on PLEs in nonclinical populations? Five databases were searched, and effect sizes were extracted for each study. Seventeen papers were included in the review. Eleven papers explored the relationship between mindfulness and PLEs, and the meta-regression found a small negative association between PLEs and mindfulness (k = 8; pooled correlation r = −0.25; 95% confidence interval [CI]: −0.37, −0.13, p < .001). Eight studies investigated the effect of MBIs on PLEs and the summary effect was not significant in the meta-analysis (k = 5; pooled standard mean difference = .09; 95% CI: −0.61, 0.79, p = 0.80). Overall, the findings suggest that higher levels of mindfulness are associated with reduced PLEs, with no evidence for the effectiveness of MBIs in reducing PLEs. Findings should be interpreted cautiously given the small number of studies and high heterogeneity in the meta-analyses. Future studies are needed to determine whether MBIs might prevent the transition to psychosis or an at-risk mental state and might usefully measure a broader range of clinically relevant outcomes.