Tag: statistics

J Matern Fetal Neonatal Med. 2026 Dec;39(1):2612841. doi: 10.1080/14767058.2026.2612841. Epub 2026 Jan 18.

ABSTRACT

OBJECTIVE: To describe risk factors for declining antepartum vaccination, including the novel COVID-19 vaccine during the COVID-19 pandemic.

METHODS: Retrospective cohort study including women delivering at a single center in the fall and winter of 2021. Patients without vaccine data were excluded. Baseline characteristics collected from the electronic medical record included maternal age, nulliparity, body mass index, insurance, and self-identified race/ethnicity. Those who accepted the COVID-19 vaccine were compared to those who declined. Separate comparisons were done to assess those who accepted and those who declined influenza and tetanus, diphtheria, pertussis (Tdap) vaccines as well. Statistical analysis was performed using Student’s t-test, Fisher’s exact test, chi square, and logistic regression. The regression model assessed the impact of patient characteristics on vaccine acceptance and was adjusted for age, nulliparity, body mass index, insurance, and race/ethnicity.

RESULTS: Vaccine data was available for 772 patients. The rate of acceptance was 46.1% for COVID-19 vaccine, 58.0% for influenza vaccine, and 80.8% for Tdap vaccine. Those who accepted the COVID-19 vaccine were older (34.3 ± 3.8 years vs 33.0 ± 4.8 years, p < 0.001) and more frequently nulliparous (8.7% vs 2.9%, p < 0.001) than those declining it. Those accepting Tdap were also older (33.8 ± 4.3 vs 32.7 ± 4.9 years, p = 0.006). Insurance type differed across groups for all three vaccines (p < 0.001). Race differed between acceptance and refusal of the influenza and Tdap vaccines, but not the COVID-19 group. In the adjusted analysis, public insurance remained independently associated with reduced acceptance for COVID-19 (aOR 0.28, 95% CI 0.14-0.55) and influenza (aOR 0.38, 95% CI 0.20-0.73), but not for Tdap. Older age and nulliparity were independently associated with increased acceptance of COVID-19.

CONCLUSION: Public insurance in pregnancy is associated with a decreased likelihood of vaccine acceptance for the COVID-19 and influenza vaccines. Specific efforts for understanding the motivations for declining vaccination are needed to develop strategies to improve uptake in this population.

PMID:41549971 | DOI:10.1080/14767058.2026.2612841

Stat Methods Med Res. 2026 Jan 19:9622802251412849. doi: 10.1177/09622802251412849. Online ahead of print.

ABSTRACT

A main interest in clinical practice is the prediction of patient prognosis conductive to decision making. Therefore, a relevant prediction model should be able to reflect the updated patient’s condition. A joint model of longitudinal markers and time-to-event data has been widely applied to estimate the association between the risk of the event and the markers’ change. The purpose of this work is to provide dynamic measures for evaluating the predictive accuracy of longitudinal markers in a context of interval-censored failure time data. We propose dynamic area under curve and Brier score reflecting incomplete data structure of interval-censored data. Simulation study compares the prediction performance of joint model and landmarking method. As a real data example, the suggested method is applied to predict the occurrence of dementia using repeatedly measured cognitive scores.

PMID:41549936 | DOI:10.1177/09622802251412849

Pol J Pathol. 2025;76(3):248-256. doi: 10.5114/pjp.2025.156555.

ABSTRACT

TROP-2 is a transmembrane calcium signaling molecule that is detected at a high rate (63%) in breast cancers. There are conflicting data on its relationship with subtypes, clinical, and pathological data in breast cancer. TROP-2 expression levels were evaluated by immunohistochemistry, and the H-score method was used to analyze the data. This evaluation was conducted on a total of 79 patients diagnosed with triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER2) positive (HER2-E) breast cancer. The study also investigated the relationship between TROP-2 expression levels and the clinical-pathological features observed in patients diagnosed with TNBC and HER2-E. A total of 62 TNBC (78.5%) and 17 HER2-E (21.5%) cases were analyzed in the study. The presence of high TROP-2 (H-score > 100) was detected in 87% of the TNBC group and 94% of the HER2-E group. Among the pathological parameters, only low H-score values were found to have a statistically significant correlation with mucinous morphology; however, no significant correlation was found with other pathological parameters, including CerbB2 expression status. No significant relationship was found between H-score and clinical parameters. Furthermore, TROP-2 expression in HER2-E cancers is notably elevated. Further studies with larger series are required to clarify expression rates in mucinous tumors.

PMID:41549930 | DOI:10.5114/pjp.2025.156555

Pol J Pathol. 2025;76(3):239-247. doi: 10.5114/pjp.2025.155817.

ABSTRACT

Malignant melanoma is an aggressive skin cancer, with immune evasion mechanisms contributing to tumour progression. This study evaluated the relationship between mismatch repair (MMR) protein loss and the expression of immune checkpoint molecules programmed death ligand 1 (PD-L1) and galectin-9. Ninety melanoma cases (60 primary, 30 metastatic) were analysed by immunohistochemistry for MMR proteins, PD-L1, and galectin-9. Associations with clinicopathological features and overall survival (OS) were assessed. Mismatch repair protein loss occurred in 5% of primary and 16.7% of metastatic melanomas (p = 0.015). Programmed death ligand 1 was positive in 18.8% of cases, with higher expression in metastatic tumours, but this was not statistically significant (p = 0.106). All PD-L1 positive tumours retained MMR proteins. Galectin-9 expression tended to be higher in tumours with MMR loss and in PD-L1-positive cases, but correlations were not significant. Median OS was 26.0 months, and no variable significantly affected survival in multivariate analysis. Mismatch repair loss was more frequent in metastatic melanomas and associated with higher galectin-9 expression, whereas PD-L1 showed no clear link with MMR status. None of the associations reached statistical significance, emphasising the descriptive and exploratory nature of the study. These findings outline biomarker expression patterns in melanoma and support further investigation in larger cohorts, including patients treated with immune checkpoint inhibitors, to clarify their potential clinical relevance.

PMID:41549929 | DOI:10.5114/pjp.2025.155817

Pol J Pathol. 2025;76(3):233-238. doi: 10.5114/pjp.2025.157906.

ABSTRACT

Nevus sebaceous (NS) is a benign hamartomatous lesion; however, benign proliferative lesions are less frequently associated with secondary neoplasms. The aim of this study is to evaluate the prevalence of secondary benign and malignant tumours seen in NS lesions, and to reveal the histopathological features of these lesions. Eighty-six NS cases were retrospectively evaluated for gender, age, lesion location, and accompanying lesions, as well as secondary benign and malignant tumours. The data obtained using descriptive statistics were analysed. 66.3% of cases were male, 33.7% were female, and the mean age was 37.8 years. 61.6% of lesions were localised on the face, 37.2% on the scalp, and 1.2% on the back. Secondary lesion development was observed in 39.5% of cases. The most common malignancy, as reported in the literature, was basal cell carcinoma. Although secondary lesions, secondary tumours, and malignancy development are rare in NS lesions, careful follow-up and surgical excision if necessary are recommended, especially in adulthood. This study contributes to the literature by revealing the pathological characteristics of secondary lesions accompanying NS, emphasising the need for careful histological evaluation of NS excisions in the differential diagnosis and raising awareness that malignancies may be present.

PMID:41549928 | DOI:10.5114/pjp.2025.157906

Stat Methods Med Res. 2026 Jan 19:9622802251412840. doi: 10.1177/09622802251412840. Online ahead of print.

ABSTRACT

The hazard function is central to the formulation of commonly used survival regression models such as the proportional hazards and accelerated failure time models. However, these models rely on a shared baseline hazard, which, when specified parametrically, can only capture limited shapes. To overcome this limitation, we propose a general class of parametric survival regression models obtained by modelling the hazard function using autonomous systems of ordinary differential equations (ODEs). Covariate information is incorporated via transformed linear predictors on the parameters of the ODE system. Our framework capitalises on the interpretability of parameters in common ODE systems, enabling the identification of covariate values that produce qualitatively distinct hazard shapes associated with different attractors of the system of ODEs. This provides deeper insights into how covariates influence survival dynamics. We develop efficient Bayesian computational tools, including parallelised evaluation of the log-posterior, which facilitates integration with general-purpose Markov Chain Monte Carlo samplers. We also derive conditions for posterior asymptotic normality, enabling fast approximations of the posterior. A central contribution of our work lies in the case studies. We demonstrate the methodology using clinical trial data with crossing survival curves, and a study of cancer recurrence times where our approach reveals how the efficacy of interventions (treatments) on hazard and survival are influenced by patient characteristics.

PMID:41549920 | DOI:10.1177/09622802251412840

Stat Methods Med Res. 2026 Jan 19:9622802251411538. doi: 10.1177/09622802251411538. Online ahead of print.

ABSTRACT

Response-adaptive randomization (RAR) can increase participant benefit in clinical trials, but also complicates statistical analysis. The burn-in period-a non-adaptive initial stage-is commonly used to mitigate this disadvantage, yet guidance on its optimal duration is scarce. To address this critical gap, this paper introduces an exact evaluation approach to investigate how the burn-in length impacts statistical operating characteristics of two-arm binary Bayesian RAR (BRAR) designs. We show that (1) commonly used calibration and asymptotic tests show substantial type I error rate inflation for BRAR designs without a burn-in period, and increasing the total burn-in length to more than half the trial size reduces but does not fully mitigate type I error rate inflation, necessitating exact tests; (2) exact tests conditioning on total successes show the highest average and minimum power up to large burn-in lengths; (3) the burn-in length substantially influences power and participant benefit, which are often not maximized at the maximum or minimum possible burn-in length; (4) the test statistic influences the type I error rate and power; (5) estimation bias decreases quicker in the burn-in length for larger treatment effects and increases for larger trial sizes under the same burn-in length. Our approach is illustrated by re-designing the ARREST trial.

PMID:41549918 | DOI:10.1177/09622802251411538

Stress Health. 2026 Feb;42(1):e70139. doi: 10.1002/smi.70139.

ABSTRACT

To assess available evidence on the association between anxiety and caffeine consumption in healthy individuals. A high-sensitivity electronic search was performed, as recommended by the Cochrane Handbook, which underwent peer review according to the PRESS Guide, in March 2021 in the following databases: Cochrane Library, MEDLINE via PUBMED, LILACS via VHL, APA PsycNet, EMBASE, Scielo, Scopus, Web Of Science and Cinahl. There were no idiomatic or temporal restrictions regarding the studies obtained. After applying the inclusion and exclusion criteria, the articles were evaluated in a paired manner by two review authors for risk of bias and quality of evidence using the ROB-II tool. Statistical analysis was conducted using R version 1.4.1106 with a fixed-effect model, but the specific statistical tests applied were not detailed. 6999 studies were located, of which 6972 were excluded following the PRISMA protocol, leaving 27 articles at the end. The findings indicate a dose-dependent anxiogenic effect of caffeine. However, variations were observed between individuals with low and high habitual caffeine consumption prior to the intervention. Additionally, evidence suggests that caffeine-induced insomnia may have contributed to increased anxiety in the study population. In general, the findings of the present study were predominantly in favor of caffeine associated with increased anxiety symptoms.

PMID:41549915 | DOI:10.1002/smi.70139

Int J Gynaecol Obstet. 2026 Jan 19. doi: 10.1002/ijgo.70816. Online ahead of print.

ABSTRACT

Preterm birth occurs in approximately 10% of all pregnancies, and is not only the leading cause of neonatal mortality but also a major contributor to short- and long-term morbidities due to immaturity. Preterm birth has also been linked to an increased risk of maternal cardiovascular and cerebrovascular diseases, making it a critical concern in both perinatal medicine and women’s lifelong health. Effective treatment requires interventions during threatened preterm labor, and several tocolytic agents have been developed and used in clinical practice. However, no pharmacological agent has been shown to prolong gestation and improve neonatal outcomes. Nifedipine, a calcium channel blocker, is widely used as a first-line tocolytic agent because of its oral administration route and relatively favorable safety profile compared with other drugs. Evidence from randomized controlled trials, meta-analyses, and Cochrane reviews suggests that nifedipine can delay delivery for a short period; however, robust evidence demonstrating sustained prolongation of pregnancy or improved neonatal survival is still lacking. Moreover, data on maternal hemodynamic changes and fetal effects are limited, highlighting the need for optimal dosing strategies and monitoring protocols. In this study, we discuss the clinical significance and limitations of nifedipine in the management of threatened preterm labor and outlined future directions. Future studies should involve large and homogeneous populations, continuous assessment of maternal hemodynamics, and application of novel biomarkers to support individualized therapy. Accumulation of such evidence is expected to optimize the management of threatened preterm labor and ultimately improve outcomes for mothers and infants.

PMID:41549889 | DOI:10.1002/ijgo.70816

Suicide Life Threat Behav. 2026 Jan;56(1):e70077. doi: 10.1111/sltb.70077.

ABSTRACT

INTRODUCTION: Bisexual individuals face elevated suicide risk, yet relatively little is known about short-term fluctuations in suicidal ideation (SI) and related constructs within this population. This study compared the frequency and variability of SI facets among bisexual and heterosexual college students.

METHOD: Sixty-two students (38 heterosexual; 24 bisexual) completed ambulatory assessments five times daily for 10 days, rating suicidal desire, wish to live (WTL), and wish to die (WTD). Analyses included generalized linear models and descriptive and variability statistics.

RESULTS: Bisexual participants reported lower WTL and higher suicide desire and WTD than heterosexual peers, with the most robust effects observed for WTD. Bisexual participants were also more likely to endorse non-zero suicidal desire and WTD and experienced more frequent large moment-to-moment changes in these constructs. Models revealed similar variability in suicidal desire and WTD across groups, whereas bisexual individuals exhibited modestly higher variability in WTL.

CONCLUSION: Findings suggested that bisexual individuals not only reported higher levels of suicidal desire and WTD but also experienced these states more frequently, with more frequent acute shifts over time. These results highlighted the importance of monitoring short-term fluctuations in suicidal thoughts and behaviors when assessing suicide risk in bisexual populations.

PMID:41549887 | DOI:10.1111/sltb.70077