Nevin Manimala

Behav Res Methods. 2026 Apr 23;58(5):137. doi: 10.3758/s13428-026-02999-x.

ABSTRACT

In nonexperimental studies, obtaining an unbiased estimate of the average treatment effect (ATE) typically requires two key assumptions: that all relevant covariates are measured (i.e., no unmeasured confounding) and that the statistical model used for covariate adjustment is correctly specified. Two common approaches for adjustment are specifying an outcome model and propensity score weighting. To mitigate bias from model misspecification, doubly robust methods combine both approaches, ensuring unbiased ATE estimates if either the outcome model or the propensity score model is correctly specified. In this study, we review four doubly robust methods that have received considerable attention in the methodological literature but remain underutilized in psychological research: augmented inverse probability weighting, regression weighted by the inverse propensity score, regression incorporating the inverse propensity score as a covariate, and calibrated propensity score weighting. Using two simulation studies, we compare these methods with regression estimation and inverse probability weighting estimators. Our results suggest that doubly robust methods-particularly regression weighted by the inverse propensity score-offer greater protection against bias from model misspecification across various data-generating scenarios. We also discuss practical considerations for implementing doubly robust methods, including weight normalization, propensity score truncation, and potential efficiency losses due to overfitting. The different methods for estimating the ATE are illustrated in a data example.

PMID:42026423 | DOI:10.3758/s13428-026-02999-x

Musculoskeletal Care. 2026 Jun;24(2):e70224. doi: 10.1002/msc.70224.

ABSTRACT

INTRODUCTION: In recent years, the Ankylosing Spondylitis Performance Index (ASPI) has emerged as a new objective measure of physical function in patients with axial spondyloarthritis (axSpA). So far, only the relative interrater reliability of the ASPI test has been reported, but the absolute interrater reliability remains to be investigated.

OBJECTIVE: This study investigated the interrater absolute and relative reliability of the ASPI test in patients with axSpA from a [Nordic] country.

METHODS: Patients with axSpA were recruited from [a Danish] rheumatology outpatient clinic between October and November 2023. The participants performed the ASPI twice with two different raters, with a 15-min pause between tests. Absolute and relative reliability were assessed.

RESULTS: Fifty-two participants were included. The standard error measurement for the overall ASPI test was 3.4%, and the minimal detectable difference was 9.5%. The participants performed the ASPI test faster with the second rater (mean 38.15 s (standard deviation, SD 12.16 s) compared to the first rater (40.92 s (SD 12.07 s)) with a statistically significant reduction in time of -2.77 s (SD 4.53 s) (p < 0.001). The intraclass correlation coefficient of the ASPI test was 0.91 (95% CI 0.76-0.96).

CONCLUSION: The study showed high absolute interrater reliability with low interrater measurement error for single individuals and groups in patients with axSpA. The relative reliability was also high. However, ASPI demonstrated a learning effect at group level. This study offers clinically relevant guidance for interpreting differences in the ASPI scores when tests are repeated by different raters, relevant for real-world clinical practice.

PMID:42026410 | DOI:10.1002/msc.70224

Arch Orthop Trauma Surg. 2026 Apr 23;146(1):158. doi: 10.1007/s00402-026-06319-y.

ABSTRACT

BACKGROUND: Upper extremity amputations are associated with developing psychiatric conditions. The aim of this study is to identify differences in mental health outcomes for patients undergoing major versus minor upper extremity amputations.

METHODS: Data were obtained from the PearlDiver database between 2010 and 2022 using Current Procedural Terminology and International Classification of Diseases codes. Patients aged 10 and above without prior mental health diagnoses or antidepressant prescription records who underwent upper extremity amputations were stratified by major (shoulder disarticulation, arm, forearm, wrist, transmetacarpal) versus minor (single metacarpal, digit, phalanx) amputations. Demographic characteristics and rates of mental health diagnoses, antidepressant prescriptions, and psychotherapy care were assessed for 90 days and one year postoperatively, using Welch’s T-tests and Pearson’s chi-squared tests.

RESULTS: Patients with major amputations had increased risk of mental health diagnoses at 90 days (OR: 3.29, p < 0.001) and at one year (OR: 2.01, p < 0.001). Both groups had higher rates of mental health diagnoses than the general population. Patients undergoing major amputations had higher odds of starting antidepressants at 90 days (OR 3.82, p < 0.001) and at one year (OR 2.38, p < 0.001). Psychotherapy care was significantly increased after major amputations at 90 days (OR 5.47, p < 0.001) and at one year (OR 4.18, p < 0.001).

CONCLUSIONS: Mental health disorders, antidepressant use, and psychotherapy care are significantly higher for major upper extremity amputations compared to minor amputations. Surgical teams should provide mental health resources to mitigate negative effects from mental health needs after upper extremity amputation.

LEVEL OF EVIDENCE: III.

PMID:42026387 | DOI:10.1007/s00402-026-06319-y

World J Microbiol Biotechnol. 2026 Apr 24;42(5):230. doi: 10.1007/s11274-026-04971-5.

NO ABSTRACT

PMID:42026382 | DOI:10.1007/s11274-026-04971-5

J Math Biol. 2026 Apr 23;92(5):75. doi: 10.1007/s00285-026-02390-6.

ABSTRACT

Neurodegenerative diseases (NDs), such as Alzheimer’s, Parkinson’s, and prion diseases, are characterized by the dynamical spread of toxic proteins through the brain. In prion diseases, cellular prion protein ( ${\text{PrP}}^{\text{C}}$ ), produced by neurons, misfolds into a toxic form, known as scrapie prion protein ( ${\text{PrP}}^{\text{Sc}}$ ). ${\text{PrP}}^{\text{Sc}}$ induces neuronal stress which ultimately leads to cell death. In this paper, we develop mathematical models for the progression of prion diseases, incorporating a cellular defense mechanism that introduces a delay term affecting protein translation and a volatility term accounting for unaccounted biological factors influencing the system. We also extend the model to capture the spatial spread of toxic proteins over the brain connectome. Our first objective is to establish the existence and uniqueness of a global positive solution to the prion disease models. Afterwards, we analyze the asymptotic behavior of the models by identifying regimes of persistence and extinction of toxic proteins. For the deterministic delayed systems, we perform a stability analysis for the persistence and demonstrate that the system undergoes a Hopf bifurcation. We also study the intensity of fluctuations of the equilibrium state of the stochastic model. Additionally, we present numerical simulations to illustrate the model dynamics using biologically relevant parameters.

PMID:42026378 | DOI:10.1007/s00285-026-02390-6

Childs Nerv Syst. 2026 Apr 23;42(1):177. doi: 10.1007/s00381-026-07270-4.

ABSTRACT

OBJECTIVE: Moyamoya disease (MMD) is a progressive cerebrovascular disorder and an important cause of childhood stroke. Surgical revascularization is the established treatment for symptomatic disease. However, comparative data examining perioperative safety and long-term outcomes between pediatric and adult patients remain limited. This study hence aimed to evaluate whether age influences postoperative complications, early neurological outcomes, and long-term stroke risk following direct and/or indirect bypass surgery.

METHODS: We conducted a retrospective multicenter cohort study of patients with MMD who underwent surgical revascularization at 13 academic centers across North America between 2008 and 2022. The primary outcomes were overall postoperative complications and long-term stroke occurrence. Comparisons between pediatric (≤ 18 years) and adult (> 18 years) hemispheres were performed using overlap propensity score weighting (PSW) to adjust for differences in baseline characteristics. Sensitivity analyses were conducted in patients with ≥ 2 years of follow-up.

RESULTS: A total of 567 hemispheres (523 adult, 44 pediatric) were included. Adults had higher rates of vascular comorbidities, whereas pediatric patients more frequently presented with congenital conditions and earlier Suzuki grades. Pre- and post-PSW analyses demonstrated no significant age-related differences in outcomes (p ≥ 0.05). On weighted regression, age was not associated with postoperative complications (OR 0.92; 95% CI 0.41-2.05), discharge neurological status (mRS: OR 1.08; 95% CI 0.52-2.21; and NIHSS: OR 0.97; 95% CI 0.45-2.10), or long-term cerebrovascular events (OR 0.88; 95% CI 0.28-2.74). On sensitivity analysis of patients with > 2 years of follow-up, no pediatric hemispheres experienced stroke compared with 12% of adult hemispheres, though this difference was not statistically significant (p = 0.14).

CONCLUSIONS: Despite marked differences in baseline comorbidities and angiographic severity, pediatric and adult patients experienced similar perioperative outcomes and long-term stroke risk after bypass surgery. These findings support the durability and safety of both direct and indirect revascularization across age groups.

PMID:42026373 | DOI:10.1007/s00381-026-07270-4

Musculoskeletal Care. 2026 Jun;24(2):e70198. doi: 10.1002/msc.70198.

ABSTRACT

INTRODUCTION: Developmental dysplasia of the hip (DDH) is a common condition that can be effectively treated if detected early. DDH screening remains institution-based with no clear guidelines at the national level in many countries, including Jordan and most of the MENA region. The aim of the study was to assess Jordanian pediatricians’ DDH screening knowledge and skills, identify associated factors, and explore readiness for a national screening approach.

METHODS: A nationwide, cross-sectional, STROBE-compliant survey was administered (Aug-Sep 2025) to 255 Pediatricians. A 19-item questionnaire assessed aspects such as risk factors, age of screening, incidence in Jordan, physical signs, confidence in performing the Barlow and Ortolani manoeuvres, and management approaches, along with their ‘composite knowledge score’ score. CKS was graded using Bloom’s cut-offs (high ≥ 80%, moderate 60%-79%, low < 60%). Factors associated with higher CKS were examined with the Welch two-sample t-test, ANOVA and Tukey post hoc tests.

RESULTS: Only 9% achieved high CKS scores, 49.4% moderate, and 41.6% low. DDH screening was routinely performed by 69.4% of participants, and 70.6% had access to hip ultrasound at their workplace. The mean overall CKS was 61.6 ± 14.6 and the mean CKS scores were 63.3 ± 14.25 for specialists and 57.7 ± 14.78 for residents; Participants with more experience, higher infant exposure, and greater confidence in performing the Barlow and Ortolani manoeuvres achieved higher scores.

CONCLUSION: Our study revealed that pediatricians in Jordan generally lack adequate knowledge and skills in DDH screening, a gap consistent across location, sector, and experience level. Higher level of experience, greater exposure to infants and higher confidence in performing Barlow and Ortolani manoeuvres were associated with better proficiency. A national training programme coupled with national guidelines is needed to promote early detection and reduce late-presenting cases.

PMID:42026371 | DOI:10.1002/msc.70198

IEEE J Biomed Health Inform. 2026 Apr 23;PP. doi: 10.1109/JBHI.2026.3687164. Online ahead of print.

ABSTRACT

Multi-label Chest X-ray (CXR) classification faces significant challenges from the inherently imperfect nature of clinical data, particularly the complex interplay of co-occurring pathologies, training data with a long-tailed distribution, and high visual similarity between distinct diseases. To address these challenges, we propose a novel framework that synergizes medical prior knowledge with prototype-driven contrastive learning, enabling disentangled and discriminative per-pathology representation learning. In particular, our approach integrates a co-occurrence modulated Label Graph Attention (LGA) module, which leverages semantic prior knowledge from a pre-trained large language model (LLM) and statistical co-occurrence patterns from training data to model inter-pathology relationships. Subsequently, a Label-Aware Decoupling (LAD) decoder is proposed to isolate pathology-specific visual features and mitigate feature suppression by dominant classes. Furthermore, we introduce an Adaptive Proto type Contrastive Learning (APCL) mechanism to enhance the discriminability of visually similar pathologies. Extensive experiments on the NIH ChestX-ray14 and CheXpert datasets demonstrate the framework’s superiority, achieving state-of-the-art mean AUCs of 0.834 and 0.840, respectively. Furthermore, cross-dataset evaluations on the external MIMIC-CXR dataset validate the framework’s exceptional zero-shot and few-shot generalization capabilities, highlighting its strong robustness and potential for real world clinical deployment. The implementation is available at https://github.com/ZengXHYX/Learning-from-Prototypes.

PMID:42024945 | DOI:10.1109/JBHI.2026.3687164

IEEE Trans Neural Netw Learn Syst. 2026 Apr 23;PP. doi: 10.1109/TNNLS.2026.3685617. Online ahead of print.

ABSTRACT

Network motifs, as fundamental functional substructures in gene regulatory networks (GRNs), play a critical role in regulating gene expression. Despite the successful application of graph representation learning in GRN modeling, most existing approaches mainly capture pairwise relationships and overlook higher order regulatory patterns encoded by functional motifs, which limits the accuracy of regulatory inference. To address this limitation, we propose Motif-GRN, a motif-based hypergraph representation learning framework that captures the underlying biological logic in higher order semantic structures. We first identify statistically significant regulatory motifs and construct a multichannel motif-induced hypergraph. We then design a motif-aware hypergraph convolutional network to extract motif-centric semantic features, while a conventional graph convolution module preserves first-order relational information. In addition, we introduce cross-view contrastive learning to align heterogeneous representations and enhance gene embeddings. Building on Motif-GRN, we develop an inductive extension that enables cross-dataset generalization and effective GRN inference with limited labels. Extensive experiments on three ground-truth networks across seven cell types demonstrate that Motif-GRN outperforms state-of-the-art baselines in both transductive and inductive GRN inference tasks, highlighting its potential for higher order regulatory network modeling.

PMID:42024938 | DOI:10.1109/TNNLS.2026.3685617

Indian J Med Res. 2026 Mar;163(3):327-333. doi: 10.25259/IJMR_452_2025.

ABSTRACT

Background and objectives The rise of antibiotic resistance is a global health crisis, and the irrational use of antibiotics is the major contributing factor. Therefore, it is essential to understand the antibiotic usage in the community to estimate the prevalence of antibiotic usage and its association with various co-variates and to evaluate the consumption pattern of antibiotic usage in the catchment areas of the Urban Health Training Centre of a medical college in Ahmedabad City. Methods An observational, community-based cross-sectional study was conducted in 3 phases during May-Aug 2024. Estimated sample size was 315 individuals who were ill anytime in last three months or consumed drugs and were selected from 15 clusters identified by cluster sampling method. Information was gathered on a structured questionnaire, and statistical parameters such as prevalence, prevalence ratios, confidence interval, and chi-square test were calculated in MS Excel. Results The screening of 2278 participants yielded 349 eligible participants as per inclusion criteria and 117 (33.5%) of them consumed 152 antibiotics during the previous three months. Sociodemographic determinates like age, sex and qualification of treatment provider showed significant association with antibiotic usage. Use of antibiotics was higher 55 (42.6%) in children than in adults 62 (28.1%). As per AWaRe classification (WHO), 3/4th of the participants (59.9%) consumed the watch group, more than half (50.4%) consumed the Access group and 2 (1.7%) consumed the Reserve group of antibiotics. Antibiotics are prescription only drugs, still in 37.5% of cases, antibiotics, even those from the Watch group, were obtained without a prescription. Interpretation and Conclusions Overall, a concerning trend of antibiotic use without prescriptions was witnessed, specifically in the ‘Watch’ category of antibiotics. It highlights the need for improved prescribing practices and public education to prevent misuse of antibiotics.

PMID:42024912 | DOI:10.25259/IJMR_452_2025