Tag: statistics

J Phys Condens Matter. 2026 Jun 4. doi: 10.1088/1361-648X/ae7886. Online ahead of print.

ABSTRACT

We present a combined light-scattering methodology for the ensemble-averaged characterization of bacterial morphology and size distributions directly in aqueous suspension. The approach integrates heterodyne near-field scattering with three-dimensional cross-correlation dynamic light scattering, providing continuous access to the scattered intensity over an extended range of scattering vectors. This configuration enables simultaneous probing of length scales associated with both the axial and radial dimensions of bacterial cells. The measured intensity profiles exhibit form-factor features characteristic of spherocylindrical particles, including oscillatory behavior arising from finite particle geometry. To interpret the experimental data, the bacterial population is modeled as a polydisperse ensemble of randomly oriented spherocylinders. Orientational averaging and population heterogeneity are explicitly incorporated into the scattering model, allowing quantitative extraction of distributions of cell length and radius for multiple bacterial strains. The calculated form factors show good agreement with experimental measurements across the full scattering range, demonstrating sensitivity to both axial and transverse polydispersity. These results establish the combined scattering framework as a statistically robust method for characterizing bacterial morphology in suspension. The approach complements microscopy-based measurements and provides a quantitative experimental basis for physical modeling of bacterial systems relevant to biomedical, environmental, and industrial contexts.

PMID:42246133 | DOI:10.1088/1361-648X/ae7886

Psychogeriatrics. 2026 Jul;26(4):e70187. doi: 10.1111/psyg.70187.

ABSTRACT

BACKGROUND: Population ageing is accompanied by increasing exposure to psychosocial challenges, including age-related stereotypes and stigma. Internalized age-related stigma has emerged as an important psychosocial factor associated with mental health and well-being among older adults. However, empirical evidence examining its associations with well-being, quality of life, depressive symptoms and perceived social support remains limited, particularly in non-Western cultural contexts.

METHODS: This cross-sectional quantitative study included 139 adults aged 65 years and older attending an internal medicine outpatient clinic. Cognitive eligibility was assessed using the revised Turkish version of the Mini-Mental State Examination. Data were collected through face-to-face interviews. Measures included the Internalized Stigma of Ageing Scale (ISAS), WHO-5 Well-Being Index, Geriatric Depression Scale (GDS-15), WHO Quality of Life-AGE (WHOQOL-AGE), Multidimensional Scale of Perceived Social Support (MSPSS), and the Attitudes Towards Ageing Questionnaire. Statistical analyses comprised t-tests, one-way analysis of variance, Pearson correlation and hierarchical multiple linear regression.

RESULTS: Participants demonstrated moderate levels of internalized age-related stigma. Internalized stigma was significantly higher among participants who were unemployed and those living alone or with adult children. Internalized stigma was negatively associated with well-being, quality of life and perceived social support, and positively associated with depressive symptoms. Regression analyses indicated that lower well-being, poorer quality of life, higher depressive symptoms and lower perceived social support were significantly associated with higher internalized stigma.

CONCLUSIONS: Internalized age-related stigma is a significant psychosocial correlate of mental well-being and quality of life in later life. Interventions targeting psychological well-being and social support may play a role in mitigating stigma-related vulnerability in later life.

PMID:42246113 | DOI:10.1111/psyg.70187

J Health Polit Policy Law. 2026 Jun 5:12650571. doi: 10.1215/03616878-12650571. Online ahead of print.

ABSTRACT

CONTEXT: Arguably, the most pressing issues in Medicare financing today center on Medicare Advantage (MA). Rising MA enrollment may lower TM spending via a spillover effect wherein cost-efficient practices in MA are applied to TM enrollees. At the same time, growing MA enrollment results in a shrinking share of TM enrollees, raising concerns about how MA plans are reimbursed, since MA payments and rebates depend, in part, on average TM spending.

METHODS: This study estimates the effect of MA enrollment shares on per-enrollee TM spending using county-level CMS data. TM spending is the product of three factors: a local price index for TM services, average price- and risk-adjusted spending per enrollee (“quantity” of services used), and average TM risk scores. We estimate the effect of MA enrollment shares on each factor.

FINDINGS: Increased MA enrollment is associated with a statistically significant reduction in TM price- and risk-adjusted spending. MA enrollment is linked to reduced outpatient service use and reduced use of procedures, tests, imaging, durable medical equipment, and ambulance services among TM enrollees.

CONCLUSIONS: Reduced spending in TM from rising MA enrollment is a form of Medicare savings that offsets, to a small degree, the substantial estimated overpayments made to MA plans.

PMID:42246093 | DOI:10.1215/03616878-12650571

Euro Surveill. 2026 Jun;31(22). doi: 10.2807/1560-7917.ES.2026.31.22.2500394.

ABSTRACT

BACKGROUNDWest Nile virus (WNV) is a zoonotic mosquito-borne pathogen increasingly reported in Europe.AIMWe aimed to characterise heterogeneities in the average annual human risk of WNV infection (force of infection, FOI) and in WNV surveillance across Europe.METHODSWe conducted a systematic review following the PRISMA guidelines to identify serological studies on WNV in humans with IgG-based assays in Europe. We then used mathematical models fitted to both age-stratified serosurvey and case data to reconstruct spatially explicit FOI estimates, the sensitivity of syndromic surveillance and age-dependent trends in case reporting.RESULTSWe extracted 92 serosurvey datasets from 21 countries. Based on 10 age-stratified serosurvey datasets from Greece, Hungary, Italy, Romania and Spain and case data from seven countries (Austria, Cyprus, Greece, Hungary, Italy, Romania and Spain), we estimated the WNV FOI for 119 European nomenclature of territorial units for statistics level (NUTS) 0-3 regions. We found evidence of spatial heterogeneities in transmission intensity and estimated that on average less than 0.2% of human WNV infections were notified, with country variability and age-dependent trends in the propensity of reporting WNV disease.CONCLUSIONThis study shows that the intensity of WNV transmission, the average annual incidence of infection and the sensitivity of surveillance are heterogeneous across Europe. Due to differences in case reporting across countries, the incidence of reported WNV cases does not necessarily reflect the same proportion of WNV infections and hence the actual infection incidence, which highlights the importance of conducting WNV seroprevalence surveys.

PMID:42246068 | DOI:10.2807/1560-7917.ES.2026.31.22.2500394

Stat Med. 2026 Jun;45(13-14):e70636. doi: 10.1002/sim.70636.

ABSTRACT

Population Attributable Fraction (PAF) is a key epidemiological measure used to quantify the contribution of risk factors to the overall disease burden. However, when an exposure affects an outcome through multiple ordered mediators, traditional PAF estimation methods face challenges in accurately identifying the impact of each mediating pathway. These challenges arise from mediator-outcome relationships, interactions among mediators, and the presence of potential confounders. In this study, we propose new measures, termed mPAFs, to quantify the fraction of disease attributable to a specific mediation pathway. The proposed framework incorporates a multiply robust estimator that yields consistent estimates of mPAFs provided that at least two of the three types of models are correctly specified: the exposure models, mediator models, or outcome model. The asymptotic properties of the estimator are formally established, and a comprehensive simulation study is conducted to demonstrate its robustness against model misspecification. In a real-data application using TCGA lung cancer cohorts, we analyzed the effect of smoking on mortality mediated through TTK and MAD2L1. In lung adenocarcinoma, the total PAF was estimated at 4.45%, with a direct effect of 1.82% and pathway-specific contributions of -1.95% (TTK) and 0.68% (MAD2L1). In contrast, lung squamous cell carcinoma showed a higher total PAF of 10.43%, with most of the effect attributable to the direct pathway (10.22%), suggesting minimal mediation via the selected genes.

PMID:42246056 | DOI:10.1002/sim.70636

Clin Teach. 2026 Aug;23(4):e70448. doi: 10.1111/tct.70448.

ABSTRACT

INTRODUCTION: Self-efficacy, the belief in one’s capacity to execute actions necessary to achieve specific objectives, is a significant predictor of academic performance and well-being in medical training. Longitudinal studies examining the dynamic evolution of self-efficacy throughout undergraduate medical education remain scarce in the Brazilian context. This study prospectively evaluated perceived self-efficacy among medical students during critical curricular transitions.

METHODS: A prospective longitudinal study followed 50 medical students from a Brazilian public university at four time points: course entry (T1-2021), end of first year (T2-2022), midpoint of clinical cycle (T3-2023) and beginning of fifth year/internship (T4-2025). The Self-Efficacy Scale for Higher Education (SESHE), a validated 34-item instrument assessing five dimensions, was administered. Statistical analyses included repeated measures ANOVA, Wilcoxon test and effect size calculations (Cohen’s d).

RESULTS: The study observed a dynamic evolution in perceived self-efficacy, characterised by a notable shift in total self-efficacy from 2021 to 2023, followed by partial recovery by 2025. This pattern included significant reductions in several dimensions. Self-efficacy in proactive actions experienced the most pronounced change (d > 0.8), while self-efficacy in social interaction demonstrated relative stability. Baseline analyses revealed higher self-efficacy in social interaction among male students (d = 0.51).

CONCLUSION: These findings suggest that the observed changes in self-efficacy represent an adaptive recalibration, moving toward a more realistic self-assessment essential for professional development. Therefore, strategies that support this healthy recalibration are crucial. These interventions should aim to facilitate adaptive adjustment, fostering robust and accurate self-efficacy throughout medical training.

PMID:42246054 | DOI:10.1111/tct.70448

Front Neurol. 2026 May 20;17:1636511. doi: 10.3389/fneur.2026.1636511. eCollection 2026.

ABSTRACT

BACKGROUND: Post-stroke depression (PSD) and post-stroke cognitive impairment (PSCI) are prevalent complications in aging stroke survivors and are often overlooked due to the lack of early diagnostic indicators, leading to poor prognosis. Identifying reliable predictors is crucial for timely intervention.

METHODS: This prospective cohort study followed 78 acute stroke survivors for 6 months. A composite neuropsychological outcome-defined as the development of PSD and/or PSCI-was determined using the Diagnostic and Statistical Manual of Mental Disorders-5th Edition (DSM-5) and NINDS-CSN criteria. To account for the limited sample size, multivariable Firth’s penalized logistic regression was employed to identify independent predictors, generating robust odds ratios (ORs) and 95% confidence intervals (CIs). An exploratory classification and regression tree (CART) analysis was also conducted for hypothesis generation.

RESULTS: The final cohort comprised 78 acute ischemic stroke survivors with a median age of 62 years (IQR 51-71). Among these participants, 26.0% were women, and the median admission score on the National Institutes of Health Stroke Scale (NIHSS) was 3 (IQR 1-5). Within 6 months, 56 patients (71.8%) developed the composite outcome (13 experienced PSCI alone, 24 had PSD alone, and 19 had both conditions). A multivariable analysis revealed that right hemisphere lesions (OR = 9.019, 95% CI: 1.329-61.213, p = 0.016), greater baseline emotional distress (higher 9-item Patient Health Questionnaire (PHQ-9) scores; OR = 5.157, 95% CI: 1.835-14.494, p < 0.001), and pre-existing cognitive vulnerability (lower Mini-Mental State Examination (MMSE) scores; OR = 0.714, 95% CI: 0.517-0.984, p = 0.023) were independent predictors of poor neuropsychological outcomes. Advanced age (p = 0.094) and elevated urea levels (p = 0.095) showed only marginal trends. Exploratory CART modeling highlighted the hierarchical interaction of these baseline clinical scores for risk stratification.

CONCLUSION: Right hemisphere lesions, early emotional distress, and baseline cognitive vulnerability independently predicted a high risk of composite neuropsychological impairment at 6 months post-stroke. Rather than serving merely as novel biomarkers, high baseline PHQ-9 scores and low MMSE scores reflected the persistence of early distress and poor cognitive reserve, respectively. These highly accessible clinical parameters facilitate early risk stratification, emphasizing the absolute need for immediate psychological triage and integrated, long-term cognitive-emotional monitoring.

PMID:42246052 | PMC:PMC13229621 | DOI:10.3389/fneur.2026.1636511

Front Neurol. 2026 May 20;17:1802303. doi: 10.3389/fneur.2026.1802303. eCollection 2026.

ABSTRACT

INTRODUCTION: Accurate diagnosis of disorders of consciousness (DoC), including unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), remains a long-standing and unresolved challenge in clinical practice. Current diagnostic frameworks rely predominantly on behavioral responsiveness, with the Coma Recovery Scale-Revised (CRS-R) serving as the clinical gold standard. However, behavior-based evaluation is intrinsically vulnerable to examiner subjectivity and cognitive-motor dissociation, contributing to misdiagnosis rates of up to 40%. From a theoretical perspective, consciousness comprises both external awareness and self-awareness, yet existing DoC assessments focus almost exclusively on external sensory processing, leaving self-awareness substantially underassessed. This imbalance highlights a critical gap that motivates for complementary assessment approaches targeting underexplored dimensions of consciousness.

METHODS AND ANALYSIS: This study protocol aims to develop an EEG-based paradigm and evaluate its feasibility for assessing gut-related interoceptive processing in patients with DoC, using controlled, non-invasive rectal balloon distension. Standardized stimulation procedures, synchronized EEG acquisition, and predefined analytical pipelines will be implemented to characterize the temporal and spatial features interoceptive event-related potentials.

RESULTS: Electrophysiological and statistical analyses will be conducted to assess the feasibility, signal characteristics, and response profiles of gut-related interoceptive EEG activity across diagnostic categories. Exploratory analyses will further examine associations between interoceptive EEG markers and clinical behavioral measures.

DISCUSSION: By systematically investigating an under assessed dimension of consciousness, this study protocol aims to establish the feasibility and signal-level characteristics of gut-related interoceptive EEG responses in patients with disorders of consciousness. By providing methodological and exploratory evidence at the group level, the findings are intended to inform the design of future hypothesis-driven and validation studies, and to support the longer-term development of complementary assessment approaches that extend beyond behavior-based evaluation, with potential relevance for clinical research and public health-oriented diagnostic strategies.

CLINICAL TRIAL REGISTRATION: [ClinicalTrials.gov], identifier [NCT07208942].

PMID:42246050 | PMC:PMC13229987 | DOI:10.3389/fneur.2026.1802303

Front Neurol. 2026 May 20;17:1846726. doi: 10.3389/fneur.2026.1846726. eCollection 2026.

ABSTRACT

BACKGROUND: Continuous positive airway pressure (CPAP) is the gold standard for obstructive sleep apnea (OSA), but its clinical effectiveness in cardiovascular risk management is often limited by suboptimal adherence.

OBJECTIVE: To systematically evaluate and compare the effects of mandibular advancement devices (MAD) vs. CPAP and inactive controls on blood pressure (BP), sleep-related respiratory events, and treatment adherence in patients with OSA.

METHODS: We systematically searched PubMed, Embase, Cochrane Library, and Web of Science from database inception to February 2026. RCTs reporting ambulatory BP outcomes pre- and post-MAD treatment were included. Secondary outcomes included the apnea-hypopnea index (AHI), Epworth Sleepiness Scale (ESS), and objective treatment adherence. Data were pooled using mean differences (MD) and 95% confidence intervals (CIs).

RESULTS: Fourteen independent RCTs (comprising 16 reports) encompassing a total of 1,141 patients, met the inclusion criteria. Compared with inactive controls, MAD showed overall trends of BP reduction. In head-to-head comparisons with CPAP, MAD demonstrated comparable cardiovascular benefits on 24-h and nighttime BP parameters. Notably, MAD achieved a significantly greater reduction in daytime systolic BP compared with CPAP (MD = -1.99 mmHg, 95% CI: -3.82 to -0.17; p = 0.03). While CPAP demonstrated superior physiological efficacy in reducing AHI (MD = 8.45 events/h, p < 0.001), MAD and CPAP yielded comparable improvements in subjective sleepiness (ESS). Crucially, pooled objective tracking data revealed that MAD had significantly longer nightly adherence than CPAP (MD = 0.71 h/night, 95% CI: 0.30 to 1.13; p < 0.001).

CONCLUSION: Despite a physiological inferiority in reducing AHI, MAD appears to offer cardiovascular benefits comparable to CPAP and demonstrates a statistically significant reduction in daytime SBP, which may be partially facilitated by its superior objective adherence. Therefore, for OSA patients who cannot tolerate CPAP, MAD may serve as a viable alternative option for cardiovascular risk management.

SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD420261303916, identifier: CRD420261303916.

PMID:42246045 | PMC:PMC13229622 | DOI:10.3389/fneur.2026.1846726

Front Neurol. 2026 May 20;17:1784525. doi: 10.3389/fneur.2026.1784525. eCollection 2026.

ABSTRACT

BACKGROUND: The Cerebellar Neuropsychiatric Rating Scale Version 2 (CNRS-2) measures affective symptoms in cerebellar disease patients across five postulated domains of attentional control, emotional control, autism spectrum, psychosis spectrum, and social skill set, each with overshoot and undershoot symptom subdomains. A data-driven approach is needed to test our a priori model and to further explore the internal structure of the scale.

OBJECTIVES: To explore the latent structure of the CNRS-2 and evaluate the five-domain and overshoot-undershoot structure of the scale items.

METHODS: CNRS-2 was administered to 279 cerebellar subjects. Data suitability for factor analysis was assessed. Eigenvalues and parallel analysis scree plots were evaluated for factor extraction. Exploratory factor analysis (EFA) was performed to identify an optimal factor solution. The EFA-derived solution and our a priori five-domain model were examined via confirmatory factor analysis (CFA). Fit indices, item loadings, and conceptual interpretability were compared. Bifactor analysis was performed on each of the five domains of the a priori model to evaluate whether variance in domain scoring was attributable to the construct measured by the domain versus two subfactors. CFA was also applied to each domain to test the validity of the overshoot-undershoot item groupings.

RESULTS: We extracted 5, 6, and 7 factors based on eigenvalues and parallel analysis. EFA indicated that a six-factor solution best balanced statistical fit and theoretical interpretability. CFA on this EFA-derived solution and on our a priori five-domain model showed both to have acceptable statistical fit and internal consistency, but the five-domain model demonstrated stronger conceptual coherence. The bifactor analysis revealed variation in the interpretability of two subfactors within each of the domains, while CFA validated the overshoot-undershoot clustering of symptoms.

CONCLUSION: Factor analysis of the items comprising CNRS-2 provided empirical support for the clinically derived conceptual framework that defines the five domains of cerebellar neuropsychiatry. Sub-analyses of the individual domains supported the overshoot-undershoot dichotomy. Convergence between our a priori domain model and the solutions derived from EFA revealed stable and interpretable symptom clusters. These findings underscore the presence of coherent, multidimensional interrelated neuropsychiatric constructs in cerebellar disease that can be identified and measured by CNRS-2.

PMID:42246044 | PMC:PMC13230212 | DOI:10.3389/fneur.2026.1784525