Category: Statistics

Am J Epidemiol. 2026 Aug 25:kwag197. doi: 10.1093/aje/kwag197. Online ahead of print.

ABSTRACT

Exclusive breastfeeding is a key pillar of healthy nutrition in infancy. While the importance of breastfeeding is undisputed, measuring early breastfeeding behavior remains challenging. This study evaluated the impact of addressing missingness in feeding variables, incorporating prelacteal feeding, reducing sampling bias through age weighting, and adjusting measurement periods on estimated exclusive breastfeeding prevalence. We show that imputing missing values reduces estimated prevalence from 42.9% (95% CI, 40.3-45.6) to 41.2% (95% CI, 38.5-44.0). Including prelacteal feeding in the definition further decreases estimates to 32.2% (95% CI, 29.5-34.8), while applying age weights slightly increased the prevalence to 33.6% (95% CI, 31.0-36.3). Measuring exclusive breastfeeding compliance at 6 months, rather than looking at average feeding behavior in the first six months of an infant’s life, yields an estimated exclusive breastfeeding prevalence of 5.9% (95% CI, 4.6-7.6). Given the major differences in exclusive breastfeeding prevalence estimates from different methodological adjustments, a standardized exclusive breastfeeding measurement is urgently needed to accurately assess early-life nutrition and guide policy based on reliable and comparable estimates.

PMID:42637574 | DOI:10.1093/aje/kwag197

Biostatistics. 2026 Jan 20;27(1):kxag030. doi: 10.1093/biostatistics/kxag030.

ABSTRACT

This paper introduces a novel decomposition framework to explain heterogeneity in causal effects observed across different studies, considering both observational and randomized settings. We present a formal decomposition of between-study heterogeneity, identifying sources of variability in treatment effects across studies. The proposed methodology allows for robust estimation of causal parameters under various assumptions, addressing differences in pre-treatment covariate distributions, mediating variables, and the outcome mechanism. Our approach is validated through a simulation study and applied to data from the Moving to Opportunity (MTO) study, demonstrating its practical relevance. This work contributes to the broader understanding of causal inference in multi-study environments, with potential applications in evidence synthesis and policy-making.

PMID:42637568 | DOI:10.1093/biostatistics/kxag030

Sex Health. 2026 Oct 20;23(5):SH26088. doi: 10.1071/SH26088.

ABSTRACT

BACKGROUND: Overseas-born gay, bisexual, and other men who have sex with men (GBMSM) experience higher HIV notification rates compared with Australian-born GBMSM. This disparity is perpetuated by delayed access to HIV testing and biomedical prevention driven by a range of factors including Medicare eligibility, language and cultural barriers, and unfamiliarity with the health system. Community-based services offer an alternative pathway to HIV testing that may better serve migrant GBMSM facing challenges accessing mainstream healthcare settings.

METHODS: We conducted a cross-sectional study comparing settings of first HIV test within our service, either peer-led community-based testing or traditional clinic-based testing for overseas-born GBMSM who arrived in Australia between January 2022 and January 2024. Participants were grouped by time of arrival to first HIV test (either less than 6 months or more than 6 months). Comparative analysis and multivariable logistic regression were used to identify characteristics associated with attendance at the community-based setting.

RESULTS: A total of 1204 GBMSM were included with 424 (35.2%) attending community-based setting for their first HIV test after arrival. Those who attended community-based testing were more likely to have arrived in Australia more than 6 months ago (66.8% vs 26.9%) and never previously tested for HIV (37.5% vs 17.2%). These factors were also associated with higher likelihood of community-based testing in the multivariable model (aOR 5.27, 95% CI 3.98-6.97 and aOR 2.13, 95% CI 1.57-2.91 respectively).

CONCLUSION: Community-based, peer-led HIV testing services play an important role in engaging overseas-born GBMSM who may be under-served by traditional clinic-based models, particularly those with longer residence in Australia and no prior HIV testing.

PMID:42637540 | DOI:10.1071/SH26088

J Neurol Neurosurg Psychiatry. 2026 Aug 24:jnnp-2026-339037. doi: 10.1136/jnnp-2026-339037. Online ahead of print.

ABSTRACT

BACKGROUND: Autosomal dominant Alzheimer’s disease (ADAD) serves as a model for presymptomatic biomarker discovery. Characterising the temporal profile of plasma biomarker levels in presymptomatic individuals may enhance understanding of disease pathogenesis, inform future clinical trials and guide clinical interpretation.

METHODS: We evaluated 124 proteins using a NUcleic acid-Linked Immuno-Sandwich Assay panel in 270 plasma samples from a longitudinal cohort study of ADAD, comprising 113 individuals (73 mutation carriers and 40 non-carriers). We determined the plasma proteomic changes that distinguished mutation carriers from non-carriers. We then used predicted age at symptom onset to determine the approximate timing of presymptomatic divergence in biomarker levels in carriers relative to non-carriers.

RESULTS: Nine proteins (amyloid-beta 42 (Aβ42), beta-secretase 1 (BACE1), glial fibrillary acidic protein (GFAP), pTau181, pTau231, pTau217, t0tal tau (MAPT), neurofilament light (NfL) and acetylcholinesterase (AChE)) robustly differed between carriers and non-carriers cross-sectionally. Longitudinal analyses showed elevated Aβ42 levels were statistically discernible in carriers approximately 26 years before expected symptom onset. Carriers diverged from non-carriers in phosphorylated tau markers at approximately 21-24 years before expected symptom onset, total tau at 19 years, GFAP and BACE1 at 14 years and NfL at 6 years. Differences in AChE were seen in symptomatic individuals likely reflecting cholinesterase inhibitor use.

CONCLUSION: Multiple plasma proteins are elevated in presymptomatic and symptomatic ADAD mutation carriers relative to non-carriers. Changes in eight biomarkers occur sequentially from 26 to 6 years prior to symptom onset. Combining biomarkers may help in staging presymptomatic AD and optimise clinical trial inclusion. Further work is needed to assess how these findings generalise to non-monogenic AD.

PMID:42637536 | DOI:10.1136/jnnp-2026-339037

BMJ Paediatr Open. 2026 Aug 24;10(1):e004598. doi: 10.1136/bmjpo-2026-004598.

ABSTRACT

BACKGROUND: Under-five undernutrition remains a critical public health challenge, but national averages frequently mask how acute vulnerabilities are socioeconomically and structurally distributed. A distributional epidemiology framework helps isolate actionable entry points for equity-oriented policy.

OBJECTIVES: To evaluate the socioeconomic and structural distribution of acute child undernutrition in Uganda and assess aetiological specificity across alternative nutritional outcomes.

DESIGN: Secondary analysis of a nationally representative cross-sectional household survey.

SETTING: Central, Eastern, Northern and Western regions of Uganda (2019/2020 round).

PARTICIPANTS: 815 children aged 24-59 months with complete anthropometric records sampled via a two-stage stratified systematic cluster design.

MAIN OUTCOME MEASURES: Childhood wasting (weight-for-height z-score<-2SD) was the primary outcome; chronic stunting and underweight served as specificity checks. Socioeconomic inequalities were quantified using concentration indices. Predictors were modelled using Firth’s penalised logistic regression to minimise small-sample bias.

RESULTS: Prevalences for stunting, underweight and wasting were 16.9% (n=138), 11.8% (n=96) and 6.1% (n=50), respectively. Macrolevel socioeconomic inequality in wasting was modest and statistically non-significant (Relative Concentration Index=-0.0085, p=0.941). However, sharp structural barriers emerged: children residing ≥4 km from a health facility faced a more than threefold increase in the odds of wasting (adjusted OR (AOR)=3.42, 95% CI 1.01 to 11.54, p=0.048), reflecting an 8.2% absolute risk expansion. This geographic barrier was uniquely specific to wasting. Female children exhibited significantly higher wasting vulnerability (AOR=4.13, 95% CI 1.62 to 10.53, p=0.003; absolute risk increase: 5.0%). Household poverty showed an unexpected inverse trend bordering significance (AOR=0.48, 95% CI 0.21 to 1.09, p=0.080).

CONCLUSIONS: Childhood wasting in Uganda is more closely linked to physical access barriers and demographic factors than household asset wealth. Mitigating acute undernutrition requires shifting from wealth-based targeting towards universal structural expansions, specifically prioritising decentralised primary healthcare and gender-sensitive community interventions.

PMID:42637528 | DOI:10.1136/bmjpo-2026-004598

J Vasc Nurs. 2026 Sep;44(3):240-249. doi: 10.1016/j.jvn.2026.07.004. Epub 2026 Jul 30.

ABSTRACT

PROBLEM CONSIDERED: Diabetic foot ulcers (DFUs) are a major global complication of diabetes, leading to high rates of disability, amputation, and mortality. Evidence suggests that inadequate knowledge, negative attitudes, and poor practices (KAP) contribute significantly to preventable DFUs, yet regional data from South Asia remain scarce. Therefore, this study aimed to assess the KAP of patients with diabetes regarding DFU prevention in Dhaka, a South Asian region, and to identify socio-demographic predictors to inform targeted interventions and health policy.

METHODS: A hospital-based cross-sectional study was conducted among 424 adult patients with diabetes at East West Medical College and Hospital, Dhaka. Data were collected using a structured, researcher-developed 30-item KAP questionnaire developed based on existing literature, with expert review, pilot testing, and acceptable internal consistency, and analyzed with descriptive statistics, Chi-square tests, and multivariable logistic regression to identify independent predictors of good KAP. Model adequacy was confirmed using the Hosmer-Lemeshow test (p > 0.05).

RESULTS: Engagement in DFU prevention was alarmingly low. Only 15.8% of participants demonstrated good knowledge, 1.7% had a positive attitude, and 4.7% reported good preventive practices. Bivariate analysis indicated a weak association between age and attitude (p = 0.046), while multivariate models revealed no significant independent predictors, indicating poor KAP was widespread across all demographic groups.

CONCLUSION: The findings demonstrate inadequate knowledge, attitudes, and preventive practices related to diabetic foot ulcer prevention among patients with diabetes in Dhaka, with the predominance of neutral responses suggesting substantial uncertainty and limited practical awareness. These results underscore the need for systematic foot-risk screening, structured patient education initiatives, and the integration of diabetic foot ulcer prevention strategies into routine diabetes management and broader non-communicable disease care services in Bangladesh.

PMID:42637496 | DOI:10.1016/j.jvn.2026.07.004

J Vasc Nurs. 2026 Sep;44(3):207-215. doi: 10.1016/j.jvn.2026.06.006. Epub 2026 Jul 14.

ABSTRACT

OBJECTIVE: To describe the demographic and clinical profile of people diagnosed with chronic venous disease (CVD) referred from primary care to a vascular specialist at hospitals in Catalonia.

DESIGN: This study used a retrospective cohort design.

METHODS: Retrospective cohort study with a sample of 265,883 people for whom sociodemographic data were available, of a total of 333,455 individuals referred from primary care to a hospital vascular specialist between 2015 and 2021. We examined sex, age, health region of origin, number of referrals per year according to stage of the disease, and comorbidities associated with the diagnosis.

RESULTS: 69.4% of the cohort were women and 30.6% men, and the mean age of the referred individuals was 61 years. For diagnoses under the heading “phlebitis and thrombophlebitis”, the number of referrals increased from 3639 in 2015 to 5200 in 2021. The proportion of venous ulcers remained fairly constant, ranging from 3.7% in 2019 to 5% in 2020. Asymptomatic varicose veins (without visible or palpable signs of venous disease) constituted 34.6% of referrals Primary hypertension and obesity were the most frequent comorbidities in all stages of chronic venous disease.

CONCLUSION: Most people with chronic venous disease referred to hospitals were female, and the proportion of phlebitis and thrombophlebitis referrals increased over the study period. A significant percentage of individuals diagnosed with asymptomatic varices were unnecessarily referred to hospitals. This phenomenon may suggest that primary care professionals need more information and training about the recommended referral criteria.

PMID:42637492 | DOI:10.1016/j.jvn.2026.06.006

Food Res Int. 2026 Oct 31;242(Pt 4):120113. doi: 10.1016/j.foodres.2026.120113. Epub 2026 Jul 22.

ABSTRACT

Elucidating the quality deterioration mechanisms of refrigerated golden pompano (Trachinotus ovatus), this study integrated 16S rRNA gene sequencing and untargeted metabolomics to systematically dissect how microbial ecological succession drives metabolic changes. As critical spoilage indicators, total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARS) continuously increased during storage, indicating significant deterioration by day 6. Microbial community succession analysis revealed that Psychrobacter, Shewanella, and Pseudomonas gradually became the dominant microbiota in the late storage stage. Metabolite enrichment analysis further demonstrated that this shift redirected the metabolic focus from early-stage nucleotide degradation to late-stage protein hydrolysis and amino acid metabolism. Moreover, multivariate statistical analysis identified 50 potential spoilage biomarkers, among which biogenic amines (histamine, tyramine, and phenylethylamine) were recognized as key indicators reflecting spoilage progression. Correlation network analysis revealed positive correlations between Pseudomonas and Shewanella abundances and the accumulation of these biogenic amines. This suggests that these two genera act as the core functional microbiota, driving spoilage metabolite generation and subsequent quality deterioration. Pathway analysis of potential spoilage biomarker generation indicates that amino acid and nucleotide metabolism constitute the core spoilage pathways, with lipid oxidation serving as a complementary mechanism. Overall, this study elucidates the spoilage mechanisms of refrigerated golden pompano, providing chemical targets for early biomarker detection and targeted antibacterial strategies.

PMID:42637441 | DOI:10.1016/j.foodres.2026.120113

Food Res Int. 2026 Oct 31;242(Pt 5):120144. doi: 10.1016/j.foodres.2026.120144. Epub 2026 Jul 31.

ABSTRACT

In the context of growing environmental concerns and the urgent need to reduce chemical inputs in agriculture, the adoption of sustainable fertilization practices has become essential. Transitioning to farming systems that minimize or eliminate the use of synthetic fertilizers can enhance soil health, meet consumer demands for safer and higher-quality products and reduce environmental pollution. This study focused on the application of probiotic-enriched compost on tomato crops, aiming to assess its impact on the fruit’s metabolomic profile, using proton nuclear magnetic resonance (¹H NMR) spectroscopy combined with multivariate statistical analysis (PCA and OPLS-DA). Compost-supplied samples were compared with those from integrated farming systems, using Demeter-organic (biodynamic) tomatoes as a benchmark. Tomatoes grown with compost showed a distinct metabolic signature, characterized by a higher sugar-to-acid ratio, while showing lower concentrations of certain amino acids. In the lipid fraction, compost-supplied tomatoes exhibited decreased in saturated fatty acids and carotenoids, including lycopene, compared to fruits from the other systems. These findings indicate that probiotic compost amendments may modulate tomato at the metabolic level. Moreover, although the reported variation in bioactive compounds suggest the need for further investigation into their balance, this work provides useful information for the optimization of organic amendments to improve quality crops within a sustainable agricultural framework.

PMID:42637325 | DOI:10.1016/j.foodres.2026.120144

JACC Cardiovasc Interv. 2026 Aug 24;19(16):2271-2273. doi: 10.1016/j.jcin.2026.06.019.

NO ABSTRACT

PMID:42637300 | DOI:10.1016/j.jcin.2026.06.019