Category: Statistics

Bone Joint Res. 2026 Jan 15;15(1):42-57. doi: 10.1302/2046-3758.151.BJR-2025-0079.R2.

ABSTRACT

AIMS: Osteoporosis poses a substantial public health burden. The conicity index (C-index), which integrates waist circumference, weight, and height, is a validated measure of abdominal obesity. However, its association with osteoporosis and femoral bone mineral density (BMD) remains unclear.

METHODS: This study analyzed data from 16,218 USA adults (aged ≥ 20 years) in the 2005 to 2020 National Health and Nutrition Examination Survey (NHANES). Associations between C-index and osteoporosis were assessed by weighted multivariable logistic regression, while associations between C-index and femoral BMD (total femur, neck, trochanter, intertrochanter) were evaluated by weighted multivariable linear regression. Potential non-linearity was explored via generalized additive models with smooth curve fitting. Threshold effect and dose-response analyses were performed, and robustness was tested by subgroup analyses.

RESULTS: After full adjustment for confounders, participants in the highest C-index quartile (Q4) had significantly higher odds of osteoporosis than those in the lowest quartile (Q1) (OR 1.67 (95% CI 1.23 to 2.27); p = 0.001). Each one-unit increase in C-index was associated with statistically significant decreases in BMD, as follows: total femur (-0.17 g/cm²), femoral neck (-0.18 g/cm²), trochanter (-0.17 g/cm²), and intertrochanter (-0.18 g/cm²). These associations persisted in subgroup analyses. A non-linear relationship was identified between C-index and femoral BMD.

CONCLUSION: Elevated C-index independently predicts osteoporosis risk and femoral BMD reduction in USA adults, with critical thresholds indicating accelerated bone loss. It thus serves as a clinically actionable metric for osteoporosis risk stratification in abdominal obesity management.

PMID:41537275 | DOI:10.1302/2046-3758.151.BJR-2025-0079.R2

Afr J Reprod Health. 2026 Jan 14;30(1):21-28. doi: 10.29063/ajrh2026/v30i1.3.

ABSTRACT

Maternal mortality remains a major public health challenge, particularly in low- and middle-income countries such as Ghana. There is limited data on timing and seasonality of maternal deaths particularly from the Sub-Saharan African region. This study examined the timing and seasonality of maternal deaths at Korle Bu Teaching Hospital, Accra, Ghana from January 2021 to December 2023. The maternal mortality ratio (MMR) was 801.3 per 100,000 live births over the period. A higher proportion of maternal deaths occurred during weekends, with Saturdays recording the highest percentage (18.5%). Deaths during night shifts accounted for 55.1% of all cases. Significantly higher proportion of maternal deaths occurred during the wet season (p < 0.001). On a month-by-month comparison, December recorded the highest MMR (1,142.1 per 100,000 live births), while November had the lowest (410.1 per 100,000 live births). More maternal deaths occurred during the night shift, weekends, wet and holiday-dense seasons.

PMID:41537253 | DOI:10.29063/ajrh2026/v30i1.3

Bioinformatics. 2026 Jan 14:btag014. doi: 10.1093/bioinformatics/btag014. Online ahead of print.

ABSTRACT

MOTIVATION: Sequence motif identification is crucial for understanding molecular recognition, particularly in immune responses involving peptide binding to MHC class I molecules for antigen presentation to T cells. Traditionally, MHC class I binding motifs are assumed to be contiguous and span nine amino acids. However, structural evidence suggests that binding may involve non-adjacent residues, challenging the assumptions of existing methods.

RESULTS: In this study, we propose GAMMA (Gap-Aware Motif Mining Algorithm), a probabilistic framework designed to identify non-contiguous motifs under conditions of incomplete labeling. GAMMA employs Bayesian inference with MCMC sampling to jointly estimate motif parameters, binding locations, and the relative spacing between binding positions. Through extensive simulations and real-world applications to MHC class I peptide datasets, GAMMA outperforms existing motif discovery tools such as GLAM2 in accurately localizing binding residues and identifying the underlying motifs. Notably, our results suggest that the true number of binding residues may be eight, fewer than the commonly assumed nine. In addition, for longer peptides, the model captures increased flexibility in the central region, consistent with structural observations that peptides may bulge in the middle.

AVAILABILITY: The raw data and the source codes are available on GitHub (https://github.com/RanLIUaca/GAMMAmotif).

SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

PMID:41537246 | DOI:10.1093/bioinformatics/btag014

J Gerontol B Psychol Sci Soc Sci. 2026 Jan 14:gbaf253. doi: 10.1093/geronb/gbaf253. Online ahead of print.

ABSTRACT

OBJECTIVES: Environmental exposures are modifiable risk factors for accelerated aging, but research is frequently limited to individual countries due to inconsistent exposure assessment. Cross-national data provides broader perspectives but adds methodological complexities. This study evaluated spatial and temporal patterns of five environmental measures assigned to older adult pseudopopulations in eight countries to highlight opportunities and challenges for aging epidemiologic studies.

METHODS: Through the Gateway to Global Aging Data project, we harmonized measures of air pollution (PM2.5, NO2, O3) and natural spaces (greenspace, blue space) for longitudinal aging cohorts in Brazil, Chile, England, India, Ireland, Mexico, Northern Ireland, and the United States. Global exposure data (1990-2021) derived from satellite observations, spatiotemporal models, and deterministic simulations were linked to 10,000 population-weighted points representing adults >50 years per country. We characterized urbanicity and area-level deprivation and examined spatial/temporal patterns to inform environmental aging research.

RESULTS: Exposure levels and variability differed within and between countries. Greenspace and NO2 exhibited high within-country variation (200% higher within-country vs. between-country standard deviations), while PM2.5 and O3 had larger across-country differences (300% higher between-country than within-country standard deviation). Temporal trends were generally consistent across countries, though unique patterns emerged (e.g., increasing PM2.5 and O3 levels in India and a radical drop in greenspace in Chile). Correlations were most consistent between NO2, greenspace, and area-level deprivation, though they varied (0.1 to 0.7).

DISCUSSION: Harmonized measures facilitate cross-country comparisons of environmental exposures but require careful consideration of confounding by place and time and differential measurement to ensure robust inferences.

PMID:41537244 | DOI:10.1093/geronb/gbaf253

Dentomaxillofac Radiol. 2026 Jan 14:twag005. doi: 10.1093/dmfr/twag005. Online ahead of print.

ABSTRACT

OBJECTIVES: Upper airway assessment is crucial due to its impact on craniofacial growth and airway-related disorders. This retrospective observational cross-sectional study aimed to evaluate the upper pharyngeal airway space volume and minimum cross-sectional area in a normal sample from Upper Egypt population, analyzing age and gender-related variations using cone-beam computed tomography.

METHODS: Ninety cone beam computed tomography scans of patients aged 18 to 60 years were evaluated. The sample was divided into three groups (Group I: ≤20 years, Group II: 21-40 years, and Group III: >40 years). Each group was further divided into two subgroups according to gender. Nasopharyngeal, oropharyngeal, hypopharyngeal, and total airway volumes, as well as the minimum cross-sectional area, were calculated using Dolphin 3D® software. Two-way ANOVA with Bonferroni post hoc test was used for statistical analysis.

RESULTS: The findings revealed significant gender differences. Males exhibited larger airway dimensions across all age groups except for nasopharyngeal volumes in adults over 20 years. A decline in airway volumes and minimum cross-sectional area in individuals over 40 years. The most constricted airway area predominantly occurred in the oropharynx. A strong positive correlation exists between minimum cross-sectional area and airway volumes. Very good inter- and intra-observer agreement.

CONCLUSIONS: Upper pharyngeal airway dimensions in a sample of the Upper Egyptian population are influenced by age and gender, highlighting the need for age and gender specific considerations in the diagnosis and treatment.

ADVANCES IN KNOWLEDGE: This study is the first to evaluate age and gender-related variations in upper pharyngeal airway volume within the Upper Egypt population. Also, it introduces a discriminant model that provides a probabilistic classification of the site of minimum cross-sectional area with 62.2% accuracy.

PMID:41537243 | DOI:10.1093/dmfr/twag005

J Invest Surg. 2026 Dec;39(1):2611440. doi: 10.1080/08941939.2025.2611440. Epub 2026 Jan 15.

ABSTRACT

BACKGROUND: Chest wall invasion is a relatively kind of infrequent direct tumor extension in non-small cell lung cancer (NSCLC) with a poor survival outcome. Risk factors that impact overall survival (OS) and cancer-specific survival (CSS) remain unclear. We aimed to explore prognostic factors and construct predictive nomograms to predict both OS and CSS in NSCLC patients with chest wall invasion.

METHODS: We extracted a total of 2091 patients between 2010 and 2015 from the SEER database. The total patients were divided into the training cohort (1463 patients) and the validation cohort (628 patients). Univariate and multivariate Cox regression analyses were applied to distinguish the independent prognostic factors. Two prognostic nomograms for OS and CSS were established. The concordance index (C-index), receiver operating characteristic curves (ROC), calibration curves, and decision curve analysis (DCA) curves were applied to assess the performance of these two nomograms.

RESULTS: After analysis, age, sex, histology, grade, N stage, M stage, surgery, and chemotherapy were identified as independent prognostic factors for OS, meanwhile, age, histology, grade, N stage, M stage, surgery, and chemotherapy for CSS. The C-index for OS in the training and validation cohorts was 0.711 and 0.716, respectively. The C-index for CSS was 0.721 and 0.726, respectively. The ROC curves, calibration curves, DCA curves, and K-M survival curves also exhibited good predictive performance.

CONCLUSION: Two nomograms provide a useful tool to predict both OS and CSS in NSCLC patients with chest wall invasion.

PMID:41537240 | DOI:10.1080/08941939.2025.2611440

Oral Health Prev Dent. 2026 Jan 15;24:1-11. doi: 10.3290/j.ohpd.c_2446.

ABSTRACT

PURPOSE: This study investigated the association between periodontitis and oral HPV infection, while exploring the role of oral bacterial microbiota diversity.

METHODS AND MATERIALS: Data from 4,685 adults in the NHANES 2009-2012 cycles were analysed. Periodontitis was defined based on clinical examination, and oral HPV infection was identified using PCR from oral rinse samples. Multivariable logistic regression models were employed to assess the relationship, adjusting for body mass index (BMI), age, sex, ethnicity, education, smoking, alcohol consumption, daily dental flossing, and history of systemic diseases. Subgroup analyses were stratified by age, sex, and education. Mediation analysis was performed to evaluate whether the oral microbiome acts as a mediator in the relationship between periodontitis and oral HPV infection.

RESULTS: No statistically significant overall association was found between periodontitis and oral HPV infection (P > 0.05). However, females with moderate to severe periodontitis exhibited increased odds of oral HPV infection (P 0.05). Oral HPV infection was associated with greater microbial diversity (higher operational taxonomic units [OTUs]). No significant mediating effect of the oral microbiome was observed.

CONCLUSION: Moderate to severe periodontitis appears to be associated with higher odds of oral HPV infection in females. These findings highlight the potential relationship between oral health, microbial diversity, and oral HPV infection.

CLINICAL IMPLICATION: In the general population, periodontitis does not appear to be a major risk factor for oral HPV; however, female with moderate to severe periodontitis and individuals with higher educati-on showed increased odds of oral HPV infection, suggesting that maintaining periodontal health may be particularly important for HPV related risk management in these subgroups.

PMID:41537224 | DOI:10.3290/j.ohpd.c_2446

Ann Ital Chir. 2025 Sep 16;97(1):119-125. doi: 10.62713/aic.3938.

ABSTRACT

AIM: This study aimed both to compare the efficacy of intravenous (IV) ibuprofen with periprostatic nerve block (PPNB) in pain control during prostate biopsy procedures and to investigate factors influencing pain scores.

METHODS: A total of 128 patients were prospectively enrolled between June and December 2023 and randomized into two groups: IV ibuprofen was Group 1 (n = 64) and PPNB was Group 2 (n = 64). Pain levels were assessed using a Visual Analog Scale (VAS) at various stages of the procedure. Demographic and clinical data, including age, prostate specific antigen (PSA) levels, prostate volume, body mass index (BMI), histopathology results, and Prostate Imaging-Reporting and Data System (PI-RADS) scores, were recorded and correlated among themselves.

RESULTS: The mean ages (64.68 ± 5.87 vs 63.33 ± 7.26 years), and median PSA level was [13.00 (8.04-41.68) ng/mL vs 10.00 (6.73-23.80) ng/mL] of Group 1 and 2 were as indicated, (p = 0.267 and p = 0.053, respectively). There were no statistically significant differences between the two groups in terms of prostate volume, BMI, PI-RADS score, and benign-malignant pathology on biopsy (p > 0.05). The median VAS scores estimated during insertion of rectal probe [4 (2-5) vs 2 (0-3)], prostate biopsy needle [3 (2-4) vs 0 (0-1)], and overall median VAS scores [4 (3-4) vs 1 (0-2)] were lower in Group 2 than Group 1 (p < 0.001 for all stages). Correlation analyses revealed that PSA levels, and malignant pathology influenced the pain scores in Group 1 (r = 0.230, p = 0.024; r = 0.268, p = 0.032, respectively). Regression analysis demonstrated that PSA levels and malignant pathology affected the overall VAS scores in Group 1 (p = 0.024 and p = 0.019, respectively).

CONCLUSIONS: IV ibuprofen demonstrates promise as an easily applicable analgesic method for prostate biopsy, particularly for patients who are unwilling or unable to undergo PPNB. This study underscores the need for large-scale investigations to validate these findings.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov with identifier (NCT06737939).

PMID:41537216 | DOI:10.62713/aic.3938

Ann Ital Chir. 2026 Jan 10;97(1):36-62. doi: 10.62713/aic.4228.

ABSTRACT

AIM: Lentigo maligna (LM) is the commonest melanoma in situ variant and frequently arises on chronically sun-exposed facial skin, where subclinical radial spread and background actinic melanocytic atypia complicate both surgical clearance and histological interpretation. The aim of this study is to appraise contemporary surgical options for LM and their oncological outcomes, focusing on conventional wide local excision (WLE), Mohs micrographic surgery (MMS), Paraffin embedded margin-controlled (“slow Mohs”) techniques and staged excision (SE).

METHODS: A comprehensive search of PubMed and Web of Science (January 2015-January 2025) retrieved retrospective cohorts, systematic reviews and meta-analyses that detailed technique, margin policy and outcomes for LM or lentigo maligna melanoma (LMM). Forty-six studies met prespecified criteria and were synthesised qualitatively.

RESULTS: WLE remains the most widely performed procedure but showed the greatest heterogeneity in practice. Initial clinical margins of 5 mm often required histological extensions to 7-12 mm to secure clearance; under WLE, residual disease rates reached 16.7% and recurrences ranged from 5.7% to 27.3%. In contrast, MMS, especially when using immunohistochemistry, achieved recurrence rates between 0-3% with ≥5 years of follow-up. Slow Mohs and staged excision provided intermediate recurrence control (0-5.7%) while preserving tissue but were limited by procedural variability and delayed reconstruction. Although one retrospective study reported improved disease-specific survival with MMS, most studies showed no significant differences in melanoma-specific or overall survival across surgical techniques. Limited long-term follow-up and inconsistent statistical reporting (e.g., confidence intervals) were common.

CONCLUSIONS: Margin-controlled approaches (MMS, slow Mohs, SE) afford superior local control to WLE and are preferable for lesions on cosmetically or functionally critical sites. Because survival appears equivalent, the choice of technique should be guided by anatomical location, lesion size, available expertise, patient characteristics and preferences as well as cost-effectiveness and available resources. Well-designed prospective trials with standardised protocols are essential to refine margin recommendations and compare long-term outcomes.

PMID:41537210 | DOI:10.62713/aic.4228

Ann Ital Chir. 2026 Jan 10;97(1):84-93. doi: 10.62713/aic.4374.

ABSTRACT

AIM: This study aimed to compare the efficacy and safety of ultrasound-guided percutaneous balloon dilatational tracheotomy (US-PDT) versus surgical tracheotomy (ST) in patients with acute respiratory failure (ARF).

METHODS: In this retrospective cohort study, 278 patients with ARF were enrolled from January 2022 to January 2025. These patients were divided into the US-PDT group (n = 135) and the ST group (n = 143) based on the surgical method used. Perioperative indicators, procedural success rates, inflammatory markers, hospitalization outcomes, and complications were systematically compared between the two groups.

RESULTS: The US-PDT group demonstrated superior outcomes across all measures. It was associated with a significantly shorter procedure time, smaller incision length, reduced intraoperative blood loss, and shorter duration of mechanical ventilation (all p < 0.001). The US-PDT group also showed a higher single-attempt procedural success rate, alongside a lower accidental extubation rate (all p < 0.001). Postoperative inflammatory markers (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and procalcitonin [PCT]) were significantly lower in the US-PDT group (p < 0.001). Furthermore, the US-PDT group experienced reduced ventilator-associated pneumonia (VAP) incidence, higher weaning success, shorter intensive care unit (ICU) and hospital stays, and lower ICU and overall mortality (all p < 0.05). Complication rates were also significantly lower in the US-PDT group (p < 0.05).

CONCLUSIONS: US-PDT is a more efficient, safer, and less invasive alternative to ST for ARF patients, resulting in better clinical outcomes, reduced inflammation, fewer complications, and improved survival rates.

PMID:41537207 | DOI:10.62713/aic.4374